SMZ 33. Panel Mounted Measuring Instrument and Recorder. User Manual. firmware version 7.x

Transcription

1 , s.r.o. Dr. M. Horákové 559, Liberec 7, Czech Republic tel , fax kmb@kmb.cz, website : SMZ 33 Panel Mounted Measuring Instrument and Recorder User Manual firmware version 7.x 01 / 2007

2 CONTENTS 1. BRIEF DESCRIPTION Instrument Connection Set up Parameter Edit Enable / Disable Summary View of Measured Quantities Star ( Wye ) Connection Delta Connection Aron Connection DETAILED DESCRIPTION Basic Features Design Description of Operation Measuring Electrical Quantities Connection Setting Up Method of Measurement and Recording Measurement Data Recording and Processing Setup in CETIS32 Software on a Personal Computer Calculation of Average Power from Recorded Average Voltage, Current, and Power Factor Values Temperature Measurement Connection Temperature Measurement Setup Output Relays Connection Function Relay Operation Setup Manual Relay Operation Real Time Circuit Synchronization Connection Function Clock Synchronization Setup Pulse Outputs Connection Function Pulse Output Setup COMPUTER CONTROLLED OPERATION Communication Links Local Communication Link Remote Communication Link RS 232 Interface RS 485 Interface

3 CAN Interface Communication Cable Terminating Resistors Remote Communication Link Protocol Description of CETIS32 Software for SMZ Setting Standard Display Ranges Instrument to Personal Computer Connection via a Local Communication Link Loading New Device in Database Device Parameter Setup (Installation) Instrument Basic Parameters Device Extended Parameters Record Setting General Information Voltage, Frequency, Temperature Current, Power Total Harmonic Distortion, Harmonic Components Daily profiles record setting Sending Record Setting to Instrument Recorded Data Transmission to Computer Use of Measured Curves Record Report Calculation of Power Export of Values to DBF file Electricity Meter Management RETIS for SMZ 33 General Default Settings Connecting Instrument to Computer and Entering into Database Instrument Database Instrument Setup Main Parameters Additional Parameters Recording Parameters Current Data Operation Energy Meter Operation Instrument Computer Control Problems, Possible Causes and Troubleshooting MAINTANENCE, SERVICE TECHNICAL SPECIFICATIONS EXAMPLE CONNECTIONS

4 1. Brief Description This chapter provides a brief description of connection and basic operation of the instrument in a typical installation. A detailed instrument description of all its features and connection possibilities follows. 1.1 Instrument Connection Instrument supply voltage at the nominal value of 230 or 115 volts (depending on device type), alternating current, is connected to the L (7) and N (8) terminals via a disconnecting device (switch see installation diagram); it must be located right at the instrument and easily accessible by the operator. The disconnecting device must be marked as such. A circuit breaker for nominal current of 1 amp makes a suitable disconnecting device, its function and positions, however, must be clearly marked (marks 0 and I, respectively, in accordance with EN ). Single phase voltages measured connect to terminals U1, U2, U3 (10, 11, 12), the common terminal for the neutral wire is identified as U N (9). It is convenient to protect the leads of voltages measured with, for example, 1 amp fuses. Figure 1 :Instrument connection The metering current transformers signals, of the nominal value 5 or 1 A AC, need to get to pairs of terminals I1k, I1l, I2k, I2l, I3k, I3l (# 1-2, 3-4, 5-6) while observing their orientation (k, l terminals). Maximum cross section of the connection wires is 2.5 square millimeters. 4

5 1.2 Set up When switching on the power, the instruments runs an inbuilt diagnostic test and updates an internal database of measured data. Doing that, it shows the following messages on the display: L1 L2 L3 SMZ 33 AHOY P Re1 Re2 M L1 L2 L3 SMZ 33 test P Re1 Re2 M L1 SMZ 33 L2 L3 init P 100% Re1 Re2 M After that, the first group of measured values is shown, usually phase voltages U1, U2, U3, and the information on the display looks then as follows (if the phase voltages or currents are connected): L1 L2 L3 SMZ P Re1 V Re M L1 SMZ A L2 L2 L L P Re1 Re2 M L1 SMZ P PF Re1 Re2 M The currently measured values can be viewed in L1 through L3 fields while the alphanumeric field shows the unit of measure or quantity name. You can switch between different inputs using the and buttons (or P and M) as illustrated in figure 2. The instrument needs adjusting to display actual values of voltages, currents and other quantities. The instrument s adjustment is determined by parameters, such as type of voltage measured (direct measurement or via metering voltage transformer with subsequent conversion), method of voltage or current connection (Star, Delta or Aron), conversion of metering current transformers, time and date of internal clock circuit, type, model and serial number of the instrument. The parameters are grouped. Each group has a number and it contains one or more parameters. The parameters are shown on pressing button P (with exceptions described further below). First group one is shown. The parameter group number is displayed in the alphanumeric field on the right (P-01), the values of all parameters of the group selected are shown in numeric fields L1 through L3. L1 L2 L3 SMZ 33 STAR STAR 230 P P-01 Re1 Re2 M L1 SMZ L2 L3 5 P P-02 Re1 Re2 M L1 L2 L3 SMZ 33 U.13 U.13 UNDE OFF P P-07 Re1 Re2 M You can scroll up and down group parameters pressing the and buttons, respectively.table 1 shows all parameters. 5

6 Table 1: List of parameters grp field parameter adjustment note name description range 0 L1 pswd edit enable (password) ---- / yes see parameter edit enable / disable 1 L1 typu type of voltage / current measured Star/ Delta / Aron L2 Unom / VTp direct measurement nominal phase value Unom [V] / V.T. primary winding [kv] V / kv L3 VTs V.T. secondary winding [kv] - / 0,1kV edit field L2 2 L1 Pnom nominal input power of measurement point [kva] kva L2 CTp C.T. primary winding A L3 CTs C.T. secondary winding 5 / 1 A 3 L1 T04 temperature at 4 ma C T04 < T20 must be true L2 T20 temperature at 20 ma C 4 L1 addr instrument address (remote communication) (1 1023) not shown in device without remote communication option kbd values in parentheses ( kbit) are for CAN L2 kbd / kbit communication rate (remote communication) L3 ptcl communication protocol P0-P1n-P1e-P1o KMB-Modbus RTU n-e-o 7 L1 R1cv relay 1 command variable type U THDI L2 R1dp command variable deviation over / under polarity for relay 1 active condition L3 R1as relay 1 active state on / off 8 L1 R1l% relay 1 command variable limit % relay function disabled if value undefined L2 R1h% relay 1 command var. hysteresis 0 50 % L3 R1bl relay one block time [min.sec.] 5 secs 60 mins 9,10 relay 2 like groups 7 & 8 12 L1 sync clock synchronization on / off not shown in device without built in el. meter L2 Erst el. meter and ¼hPmax reset --- / rst ditto L3 Prst ¼hPmax reset only --- / rst 14 L1 N1/k output 1 pulse coefficient 1 xxx [pulse/k] L2 N2/k output 2 pulse coefficient 1 xxx [pulse/k] L3 Ntyp output 1, 2 command var. type AI / AE / RL / RC 20 L1 time Real Time Circuit time HH.MM - L2 day Real Time Circuit date DD.MM - L3 year Real Time Circuit year YYYY - 30 L1 SMZ instrument type and model E,R,T, -2,-5,-C can not be changed L2 ser. serial number - L3 ver. (error number), firmware version - 6

7 In a typical arrangement, only current metering transformer conversion needs to be set. The following example describes the method of setting: Example : Current signals are connected via a current metering transformer with ration 150 / 5 A. Current metering transformer conversion is in parameter group 02 so first this group is scrolled to. Pressing button P turns on a light emitting diode (LED) at field L1 and Pnom is displayed in the alphanumeric field indicating that the L1 field parameter is the measurement point (transformer) nominal power. L1 L2 SMZ P-02 Re1 Re2 P L1 L2 SMZ Pnom Re1 Re2 L1 L2 SMZ CTp Re1 Re2 long P L3 5 L3 5 L3 5 P M P M P M L1 L2 SMZ CTp Re1 Re2 L1 x-times L2 SMZ CTp Re1 Re2 P L1 L2 SMZ CTp Re1 Re2 L3 5 L3 5 L3 5 P M P M P M Pressing the L2 field LED gets lit. The CTp information gives the current metering transformer s primary winding nominal value. The value (500 shown above) needs changing to 150 by putting this parameter in the edit mode first, pressing button P and holding it pressed for a while. As soon as the display starts flashing, release button and select the value desired using the and buttons. The edit mode is closed by pressing button P momentarily. Pressing the button again, the L3 field LED goes on and the CTp information indicates this is the current metering transformer secondary winding value. The value in the example above corresponds to the desired setting so it does not need changing. Finally return to the parameter main branch by pressing button P momentarily once more to scroll to another group or press button M to switch display to currently measured values (this display is switched to automatically in about 30 seconds from the last button press). You can edit the other parameters in an analogous manner Parameter Edit Enable / Disable The instruments are shipped in the enabled mode, that is you can edit the parameters as you like as described above. After setting the instrument up, parameter editing can be disabled, thus protecting the instrument from unauthorized operation. The information about editing being enabled or disabled can be found in parameter group 00. There is only one piece of information, in field L1. There can be one of the following: --- password not yet entered, parameter edit disabled YES password entered correctly, parameter edit enabled The parameter edit enable or disable conditioned is retained in the instrument even on power off. 7

8 If the password is not entered correctly, the instrument parameters can not be changed. Password is entered in a way similar to editing parameters: 1. Switch the instrument into the parameter view mode by pressing button P and locate parameter group 00. Select the first parameter in field L1 by pressing button P momentarily the LED next to this field gets lit and the name of the parameter, pswd, is shown in the alphanumeric field. 2. Press button P and hold it pressed until the information in field L1 starts flashing a random number is displayed there at that moment. Assuming a simple example of having a flashing number 1234 displayed. 3. Follow a sequence of pressing four buttons:,,,. The information in field L1 changes accordingly to: , so the value shown after the button press sequence is the same as before. 4. Press button P. The display shows YES to indicate correct password entry so parameters can be edited. The number displayed in password entry field is generated in random and it is not important for correct password entry (it is to confuse a hacker). What is important is only the sequence of buttons pressed. After correct password entry, parameter edit mode is enabled until it gets disabled by the operator. The parameter edit enable or disable conditioned is retained in the instrument even on power off. Parameter edit disable mode is switched to on (intentional) pressing buttons different from the correct password entry sequence. 1.3 Summary View of Measured Quantities Using the buttons you can scroll through between all input types measured as shown in figure Star ( Wye ) Connection Basic phase elements such as voltage (U), current (I), power factor (PF) and phase shifts (P active, Q reactive, S apparent) can be viewed by phase (U-I-PF, P-Q-S) or by input (U-U-U, P-P-P, and so on); button M switches over the modes. In by phase mode of view the alphanumeric field displays in turns the phase viewed (L1 through L3) and the quantity s unit for the value shown in the numeric field indicated by a lit LED. L1 numeric field shows U (or P), L2 shows I (or Q) and field L3 shows PF (or S). The three-phase power 3P, 3Q, and 3S is displayed in an analogous way. Button M can switch units displayed between kw, kvar, kva and percentage of nominal power (as entered in parameter group 2). Line voltages U12, U23 and U31 can be displayed in appropriate window too. A group of values of electric work can only be displayed in instruments of line E which have a built in electricity meter. These instruments record separately active power consumed (A+, import) active power supplied (A+, export), reactive power inductive (ArL) and reactive power capacitive (ArC) for three time zones of different cost rates. You can further monitor the value of the maximum quarter an hour three phase active power (¼hPm) in this groups, including the time of its occurrence as recorded since last reset the last reset time is shown in the last window of this group of values. The electric work values A+, A-, ArL, ArC and the quarter an hour maximum can be reset in parameter group 12. The last two groups of values show values of the total harmonic distortion (THD) and level of each harmonic component up to order 25, in percent for each phase voltage and current. You can scroll up and down between the electric work group and harmonic component group windows using the M and P buttons. In the other groups pressing button P causes jump to parameter display. 8

9 Figure 2: Summary of quantities displayed U1 U2 U3 U1 I1 PF1 I1 I2 I3 M U2 I2 PF2 PF 1, 2, 3 U3 I3 PF3 U12 U23 U31 P1 P2 P3 Q1 Q2 Q3 cos 1,2,3 3PF f T P1 Q1 S1 M P2 Q2 S2 legend: Ux... phase voltage Uxy... line voltage I... current PF... real power factor 3PF... real three phase power factor cos... fund. harmonic power factor f... frequency T... temperature P... active power Q... reactive power S... apparent power 3P/3Q/3S... three phase P/Q/S A+.. active work, demand (import) A-... active work, delivery (export) ArL... reactive work, inductive ArC... reactive work, capacitive ¼hPm... quarter an hour maximum three phase power THD U...voltage distortion harmonic x.h U...xth harm. voltage component THD I... current distortion harmonic x.h I... xth harm. current component S1 S2 S3 P3 Q3 S3 3PQS [k] M 3PQS [%] M A+ A- ArL ArC ¼h Pm clr. time P THD U 3.h U 5.h U h U 24.h U THD I 3.h I 5.h I h I 24.h I Delta Connection In this mode line voltages are displayed and registered : U12 in L1-field, U23 in L2-field and U31 in L3- field. As neutral wire is not connected, phase voltages and other phase quantities ( power, PF, cos ) are referenced to the potential of geometrical centre of the voltage phasors connected Aron Connection In this mode the instrument measures and displays only two line voltages: U12 (in field L1) and U32 (field L3). The same applies to total harmonic distortion and harmonic components in voltage signals. The currents are measured and visualized in all phases whose signals are connected. The phase power factors have no significance in this configuration and therefore are not displayed. 9

10 2. Detailed Description 2.1 Basic Features The instrument has been designed to monitor a record voltage, current, power factor, frequency, power, work, harmonic components and total harmonic distortion in voltage and current in three phase low voltage, high voltage and very high voltage grids. Besides the electrical quantities it also allows to measure and record temperature. The instrument features inputs for three voltage signals of nominal voltage up to 3 x 440 V AC ( both direct connection and through voltage metering transformers ) and three fully isolated current inputs 1 A / 5 A AC (from current metering transformers outputs). The T model further features an input for a temperature sensor with 4 20 ma output. Power supply is required by isolated voltage of 230 or 115 V AC at Hz (depending on model). The instrument measures the true root mean square value of voltages and currents. It further evaluates both actual power factor (PF, lambda) for each phase separately or all phases together and phase power factor of fundamental harmonic components (cos φ). Measurement of the level of total harmonic distortion (THD) of voltages and currents as well as of each harmonic component separately takes place up to the 25 th order. The function of two inbuilt relays with reverse switching contacts can be programmed to follow the values measured. The E model instruments feature inbuilt electricity meter circuitry and they can be utilized as three rate four quadrant auxiliary electricity meters. This model further features a clock synchronization input (minute / quarter an hour) and two pulse outputs to send out active or reactive power (transmission electricity meter). 1MB memory and a real time circuit backed up with an inbuilt accumulator or cell allow recording of the measurement data. These can be, using a local RS 232 communication link or, if the instrument has it, a remote communication link (RS 232, RS 485, CAN) transmitted, visualized and further processed on a Personal Computer. The PC software supplied, CETIS32, provides archiving, displaying, viewing and comparing the curves measured in a graphic form and a number of other functions. The instrument s basic parameters can be set using an integrated keyboard and display. The instrument can also be used as a multifunctional panel meter without using a computer. 2.2 Design SMZ instruments are built in plastic boxes in compliance with DIN 43700, designed for installation in a switchboard panel. The installation opening needs to be 138 x 138 mm. After putting in the opening the instrument can be attached with brackets that are included. The instrument s panel has three numeric fields, L1, L2, L3, and one alphanumeric field, consisted of LED displays providing legibility even in unfavorable lighting conditions at a distance of a few meters. A four button keyboard allows moving around the display windows and setting the instrument s basic parameters. To set and transmit the curves measured the instrument features a local communication link, RS 232, marked as COM (see this manual s cover). The back panel has up to five connectors (depending on model) for connection of measurement signals, relay outputs, possibly pulse outputs, clock synchronization, remote communication link (see figure 3). Maximum cross section area of the wires connected is 1.5 square millimeters. 10

11 Figure 3: SMZ 33 back panel L O A D 1A 1A 1A 1A L1 L2 L3 N k l k l k l T SMZ-33 E R T / CAN Serial No.: U : 230 V AC / 42~80 Hz, 10VA IP 4X Made in Czechia 2.3 Description of Operation Measuring Electrical Quantities Connection Example connections are described in the appendix Power Supply Voltage The instrument requires power supply voltage 230 V AC (or 115 V AC) at 40 to 80 Hz for its operation with input power maximum 10 VA. The power supply voltage is connected to terminals 7 (L) and 8 (N). There is an internal single fuse T0.1L (T0.2L) to provide circuitry protection. Since the instrument does not have its own main switch, it is necessary to include a disconnecting device in the power supply circuit (power switch see installation wiring diagram in the appendix). It must be located right at the instrument and easy to reach by the operator. The equipment disconnecting device must be marked as such. A circuit breaker for nominal current of 1 amp makes a suitable disconnecting device, its function and positions, however, must be clearly marked (marks 0 and I, respectively, in accordance with EN ) Measurement Voltages The star connected measurement voltages go to terminals 10 (U1), 11 (U2), 12 (U3) and 9 (U N, neutral). The measurement voltage inputs are galvanically isolated from power supply inputs. If measuring indirectly via voltage metering transformers, it is necessary to enter the voltage metering transformer ratio when setting up the instrument (the VT parameter). In delta connection terminal 9 is usually not connected the potential of geometrical centre of voltage phasors connected will appear on it. 11

12 In Aron connection the phase 2 voltage is connected to terminal 9 (U N) and terminal 11 (U2) is not connected. It is suitable to protect the leads with fuses 1 A. The connection is overviewed in the following table. Table 2: Connection of measurement voltages terminal name connection method # star (wye) delta Aron 10 U1 phase 1 voltage phase 1 voltage phase 1 voltage 11 U2 phase 2 voltage phase 2 voltage - 12 U3 phase 3 voltage phase 3 voltage phase 3 voltage 9 U N neutral wire - phase 2 voltage Measurement Currents Current metering transformer outputs are connected to terminal pairs 1 2 (I1k - I1l), 3 4 (I2k I2l), and 5 6 (I3k I3l). You can use a current metering transformer of the nominal output current 5 A or 1 A. The current metering transformer ratio needs to be entered when setting up the instrument (CTp and CTs parameters). It is necessary to observe connection orientation of the current metering transformer else power factor, power and electric work values will not be evaluated correctly. In Aron connection, it is sufficient to only measure currents I1 and I3 to evaluate three phase power factor, three phase power and electric work. The phase 2 current can be connected and measured optionally; it has no effect on measuring and evaluating the values mentioned. The relevant connector features a screw lock to prevent accidental pullout and unwanted break in the current circuit Setting Up Parameter groups 1 and 2 are for setting the instrument up. In group 1, field L1, it is necessary to select connection method (typu), the choice being StAR ( wye ), DELT ( delta ) and ARON connection. In fields L2 a L3 you have to select type of connected voltage (VT). For direct measurement, the field 3 is empty and you can select nominal phase voltage Unom to one of typical value 115 / 127 / 230 / 254 V AC in L2 field. Proper selection of the nominal value is not needed for basic device operation - it is necessary for advanced functions such output relay setting and further statistic processing in CETIS32 program. If measuring via a voltage metering transformer (VT), you have to select one of typical voltage transformer ratio at the field 2 (VTp, primary voltage in kv) and field 3 (VTs, secondary voltage in kv). For example, if using a voltage metering transformer with transformation 22 kv / 0.1 kv you select 22.0 kv in field L2 and kv in field L3. In case no predefined ratio is suitable, you can select the ratio arbitrarily through the CETIS32 program. When measuring via VT, nominal voltage for relay function and statistic processing is VTp, displayed in L2 field. In parameter group 2 you can set the following parameters: nominal power of node measured and current metering transformer ratio. Measured node nominal power (Pnom, such as power supply transformer power) in kva is in field L1. You only need to set this value if you want to monitor load (power) not only in absolute values but also as nominal power percentage. If not, this parameter need not be set. On the opposite, current metering transformer ratio has always to be set you have to set 12

13 the current metering transformer primary current nominal value (CTp) is to be set in field L2 and secondary nominal current (CTs) is to be selected 5 or 1 A in field L3. In star connection three phase voltages and three phase currents are measured. Three line voltages are measured too as additional information. In delta connection three line voltages are measured and registered as main network voltages. Phase voltages and other phase quantities ( power, PF, cos ) are evaluated too as additional information these values are referenced to the potential of geometrical centre of voltages connected. In Aron connection only two line voltages U12 (shown in field L1) and U32 (field L3) and to currents, I1 and I3, are measured. Besides manual setup the instruments can also be set up using Personal Computer software CETIS32. The setup process is described in Computer controlled Operation Method of Measurement and Recording This chapter describes the principles of measuring and evaluating electric quantities. Knowing these principles is useful for correct interpretation and further processing of measurement data Frequency of Measuring, Record of Average Values The instrument carries out a single measurement of all inputs connected about every 3 seconds (except total harmonic distortion and harmonic components, see description further below). Each currently measured input value is displayed and processed in accordance with record setting: the input value is averaged during the record interval or maximum or minimum value is recorded or the last value measured. Such a value is stored at the end of the record interval. When the instrument memory is full of curves measured, the behavior depends on the settings. If the Keep Measuring mode is not selected, the instrument stops recording on full memory until it is reset. If it is selected, recording goes on and new measured values overwrite the oldest recorded values. The instrument thus remembers the latest curve of quantities that are set, the length of which corresponds to the instrument memory capacity Preparing to Measure Voltages and Currents Before each measurement of all measured inputs (that is about each 3 seconds) first frequency measurement at the U1 voltage input takes place. This measurement gives the instantaneous wavelength of the signal measured which is utilized in measuring and evaluating all alternating current signals, that all such voltages and currents. From that is ensues that all voltages and currents measured need to be of the same frequency (or the same frequency of the dominant harmonic component). It is further assumed that such a frequency does not change within the single measurement of all quantities measured, that is within an interval of about 2 seconds. In the opposite case, an additional error is generated Voltage Measurement The instrument measures true root mean square value. Measurement of signal with dominant fundamental harmonic of Hz is assumed. The instrument measures signal of four consecutive cycles (usually 4 x 20 = 80 ms) while each of the cycles is sampled in 64 points. It calculates the arithmetic average of the four recorded cycles and an effective value is calculated from the average cycle using the following formula: U eff = 1 n n i = 1 Ui U eff voltage effective value U i voltage sample measured 2 [ V ] [ 1 ] 13

14 Current Measurement The same applies to current measurement as to voltage measurement Power Factor Evaluation The instrument evaluates the actual power factor ( λ lambda, for easier displaying called PF = Power Factor) and fundamental harmonic component power factor of each phase, cos φ (suitable, for instance, for checking a compensator). The actual power factor is evaluated from the ratio of active and apparent power (for method of measurement see further below) using the following formula: P PF = [ - ] [ 2 ] S PF actual power factor P active power S apparent power in dependence on the phase difference between fundamental harmonic components of voltage and current and thus expresses inductive or capacitive character of the reactive power. figure 4: identification of consumption supply and character of reactive current in dependence on phase difference quadrant II active consumption capacitive character U50 I50a Ia+ ϕ quadrant I active consumption inductive character I50 IrC I50r IrL quadrant III active supply capacitive character Ia- quadrant IV active supply inductive character The instrument further evaluates the total three phase power factor using the formula: 3P 3 PF = [ - ] [ 3 ] 3S 3PF actual three phase power factor P three phase active power S three phase apparent power 14

15 Notes: In Aron connection only total three phase power factor is evaluated, single phase power factors are not evaluated. For the use by CETIS32 software the power factor and three phase power factor value have an attribute L or C depending on the polarity of the cos φ fundamental harmonic component power factor evaluated. The instrument s display does not show this additional information with power factor values. Besides the actual power factor for each phase (not in Aron connection) also cos φ fundamental harmonic component power factor using Fourier transformation is evaluated. The cos φ value contains the L or C attribute depending on the apparent power character measured (inductive or capacitive character as in figure 4). If average power factor value recording is set, the instrument evaluates the average value from both groups of power factor values measured, that is inductive and capacitive, separately. When storing in the memory it then stores the average value of the group that dominated during the record interval (it took a longer time) Single Phase Power Evaluation The instrument measures and evaluates the actual active power in accordance with the defining equation 1 P = n n i = 1 Ui Ii P active power U i voltage sample measured I i current sample measured [ W ] [ 4 ] In the evaluation 64 measured samples of voltage and current per cycle are included. With positive result value the condition is considered demand (import) of active power. If the result value is negative, it means the energy is flowing in reverse direction to the instrument s connection (orientation of k, l current terminals) and such a condition is considered delivery (export). Apparent power is evaluated in the formula S = Ueff Ieff [VA] [ 5 ] S apparent power U eff voltage effective value I eff current effective value Reactive power is evaluated from active and apparent power using the formula 2 2 Q = S P [ var ] [ 6 ] Q reactive power S apparent power P active power Analogously to power factor the reactive power value is completed with an attribute L or C depending on phase difference of fundamental harmonic components of voltage and current thus expressing inductive or capacitive character of the reactive power Three phase Power Evaluation Three phase power is evaluated by the instrument in calculation from each phase power. Three phase active power is yielded from simple addition as in the equation 15

16 3P + P = P1 + P 2 3 [ W ] [ 7 ] 3P three phase active power P 1, P 2, P 3 single phase active power This sum includes each phase power with polarity (positive for consumption, negative for supply). That is why correct orientation of current sensor connection is essential in three phase active power evaluation. In a similar fashion three phase apparent power is evaluated: 3Q Q Q + Q = [ var ] [ 8 ] 3Q three phase apparent power Q 1, Q 2, Q 3 single phase active power Inductive / capacitive character is expressed by +/ sign with apparent power and opposite values of single phase power gets deducted from each other. Note: With contents of higher harmonic components, each phase reactive power is consisted not only of phase shift between fundamental harmonics of voltage and current, but partially also of distortion power of higher harmonic components. Phase reactive power is, however, evaluated as a whole (the contribution of distortion power to the total phase reactive power is not evaluated by the instrument) and they are assigned a polarity sign depending on shift of fundamental harmonic voltage and current. With an unbalanced system (reactive power has different L/C characters in each phase) or when measuring in Aron connection a condition can develop in which the sum of phase reactive power of opposite L/C characters, parts of reactive power corresponding to distortion power are deducted from each other. In such a case the absolute three phase reactive power value evaluated is lower than actual and there is an additional measurement error. Three phase apparent power is evaluated using the formula 2 2 3S = 3P + 3Q [ VA ] [ 9 ] 3S three phase apparent power 3P three phase active power 3Q three phase reactive power Apparent power, single phase and three phase, have no polarity signs. If average power measurement is set, the instrument measures and evaluates instantaneous power at relevant inputs in a way described above. It calculates average power from the instantaneous power values within a measurement interval and the average value is stored in the memory at the end of the recording interval Total Harmonic Distortion and Higher Harmonic Components Evaluation The instrument evaluates each relative harmonic component up to the order of 25 from the voltage and current curves measured using Fourier transformation (h Ui, h Ii, evaluated from absolute amplitudes of harmonic components H Ui, H Ii as H Ui/H U1, H Ii/H I1). It calculates the harmonic distortion value from the components evaluated using the formulas: 25 2 THD U = h Ui [ % ] [ 10 ] i= THD I = h Ii [ % ] [ 11 ] i= 2 16

17 THD U voltage total harmonic distortion h Ui... i th relative voltage harmonic component (relative to fundamental harmonic component value H U1, i = harmonic order) THD I current total harmonic distortion h Ii... i th relative current harmonic component Since calculation of harmonic components is very time consuming, it is carried out after each measurement cycle always only for one of curves U1, I1, U2, I2, U3, I3, in this order. The harmonic component and total harmonic distortion current values are thus updated six times more slowly than other measured values, approximately every 20 seconds. The instrument is not able to record fluctuations in these values of a shorter period Evaluation of Maximum Quarter an Hour Average Active Power The E model instruments allow displaying maximum quarter an hour average three phase active power over a monitored period of time (¼hPm, 1/4P displayed). The instrument continually measures average active power and using the inbuilt real time circuit it carries out an evaluation every quarter an hour starting at the hour. If the average active power at the end of a quarter an hour elapsed is higher than previously recorded maximum value, the former replaces the latter. At the same time date and time of the value measurement is recorded. The values can be shown in the ¼hPm window (see Figure 2). The quarter an hour maximum value in kw is shown in field L1, field L2 shows the date stamp in the DD.MM format, field L3 shows the time stamp in the HH.MM format. The year is not shown. quarter an hour maximum power value date stamp L1 L2 SMZ /4P Re1 Re2 time stamp L P M The quarter an hour maximum value measured can be reset at the beginning of the period monitored by setting the Erst parameter in parameter group 12. The time of reset is stored and it can be checked in the Rst. window. Warning!!! By resetting this value you also reset the electricity meter reading!!! Electric Work Measurement (electricity meter) The E model instruments have an inbuilt circuit of four quadrant three phase electricity meter which can be utilized as an auxiliary electricity meter as well. L1 L2 L3 SMZ P kwh Re1 Re2 M 17

18 The electric work values measured are recorder in separate counters by character, that is separately active power consumed (A+, import), active power supplied (A, export), reactive power inductive (ArL) and reactive power capacitive (ArL). In each of the windows, A+, A-, ArL, ArC, you can view the corresponding power value in kwh measured. The information has the NNN NNN NNN.N format, that is it has 9 digits before and one after the decimal point. It is shown consecutively in fields L1 through L3, that is the highest order digits are in field L1, the next three lower order digits are in field L2 and the three lowest order digits before the decimal point and one after the decimal point are in field L3. The example above shows the electricity meter value kwh. The electricity meter reading can be reset at the beginning of the period monitored by setting the Erst parameter in parameter group 12. The time of reset is stored and it can be checked in the Rst. window. Warning!!! By resetting this value you also reset the electricity meter reading!!! Note: If controlling the electricity meter using a computer, up to three rate zones can be set and consumptions in each rate zone monitored separately. The instrument display, however, can only show the consumption sum over the period monitored with no regard to the rate zone setting Daily profiles evaluation In some cases, for example when checking load at distribution network node, there is not necessary to process complete continuous record of period measured, but only so-called Daily profiles can be sufficient. Daily profile is day-long record of voltages, currents and power factors with 1 minute recording interval. Average values of the quantities are recorded. Setting of daily profile (such as number and type of quantities, recording interval etc.) is fixed and cannot be changed by user. Instrument can record two types of daily profiles : selected daily profile (S-profile, or selected profile) maximum current daily profile (M-profile, or maximum profile) Both of profiles have the same structure, they differs from each other in recording day setting only. Selected profile recording day can be freely specified by user. After setting the date and sending it to the instrument with Send record date button, previous daily profile record in instrument s memory is deleted. When preset day passes, new selected daily profile is created and can be downloaded to the PC. Maximum profile record is updated when maximum of quarter an hour moving average of sum of one-minute average current values I1+I2+I3 occurs. Evaluation principle is as follows : With Maximum profile reset button, new maximum profile evaluation is started. Every minute average values of voltages, currents and power factors are evaluated and stored to auxiliary memory. At the same time, moving average of sum of minute average current values I1+I2+I3 is calculated. If this value exceeds previous maximum value, new maximum value with time stamp is stored to auxiliary memory and when the day passes, new maximum profile is updated. After that the maximum profile can be downloaded to the PC. Not only quarter an hour moving average of current sum, but quarter an hour moving averages of each current I1, I2 and I3 with their time stamps are registered too and can be checked with Receive actual state button in Daily profiles window. 18

19 Measurement Data Recording and Processing Setup in CETIS32 Software on a Personal Computer Calculation of Power in CETIS32 Software The SMZ33 instruments can be set to measure and record average power. If the instrument has not been set to record average power, the CETIS32 software allows additional calculation of active, reactive and apparent power from the voltage, current and power factor values measured. The calculation follows these formulas: P = U I PF [ W ] [ 12 ] Q 2 = U I 1 PF [ var ] [ 13 ] S = U I [ VA ] [ 14 ] P active power Q reactive power S apparent power U voltage effective value I current effective value PF power factor (or cos φ) If calculating power from U, I, PF (or cos φ) curves measured, it is, however, necessary to take the following facts into account Instantaneous Power Calculation It is usually required to establish maximum power in a phase over a period of time monitored. The instrument does, however, not measure maximum power directly it measures U, I, and power factor, separately. The problem of determining exact maximum power lies in the fact that when recording of, for example, maximum current and maximum power factor are set, it is not guaranteed that both values measured took place in the same point of time the power value calculated from values that were not measured at the same moment makes no sense. Figure 5 shows an example of such a situation. Figure 5: Sampling in accordance with setting U maximum I maximum cos maximum U end of record interval I cos 15:15 15:20 15:21 15:26 15:30 If recording of maximum voltage, maximum current, maximum power factor and 15 minute record interval are set, the voltage value measured, in this example, at 15:26, the current value measured at 19

20 15:20, and the power factor value measured at 15:21 are stored at the end of the record interval, that is at 15:30. The calculation of active power yields unreal value. To evaluate power correctly in such situations the CETIS32 software allows to set a preferred method of sampling each phase quantity (voltage, current and power factor) Sampling in Accordance with Setting In this basic sampling method, each quantity is evaluated separately and independently, that you can set recording of, for example, maximum voltage, minimum current and average power factor values at the end of the record interval. Calculation of power in this situation, however, does not make sense since it yields unreal values Slice Sampling If this sampling method is set, a slice command variable is selected. The slice command variable selected can be set to either extreme, that is maximum or minimum, and sampling of the other phase quantities is then triggered by occurrence of the extreme set for the command variable selected in the phase given (see Figure 6). You can select the following quantities to be slice command variables: voltage current power factor active single phase power active three phase power If the slice command variable is voltage, current or power factor, you can select recording by maximum or minimum of the quantity. If the command variable is power, recording of quantities takes place at the moment of detecting the power s maximum. Figure 6: Sampling by maximum U maximum U3 maximum U1 maximum U2 U[V] I [A] 15:15 15:18 15:22 15:27 15:30 phase 1 phas0 2 phase 3 20

21 Figure 6 shows an example of measuring a three phase outlet (power factor curves are not shown). If sampling by voltage extreme is set and maximum of this quantity is selected, the following values are recorded at the end of the record interval (at 15:30): U1 maximum voltage value within the whole record interval, measured at 15:22, and I1 and cos1 values measured at the same moment U2 maximum voltage value within the whole record interval, measured at 15:27, and I2 and cos2 values measured at the same moment U3 maximum voltage value within the whole record interval, measured at 15:18, and I3 and cos3 values measured at the same moment In slice recording it is then guaranteed that all quantities of one phase are sampled at the same moment. So single phase power can be calculated from them. The moment of sampling can be different in different phases so three phase power can not be calculated. If the command variable is three phase power, all phase quantities in all phases are sampled at the same moment and calculation of three phase power can be carried out. Non phase quantities, such as frequency and temperature, are not affected by slice sampling setting in any ways and they are recorded independently and in accordance with their setting. Recording of average power is not affected by the slice sampling setting in any ways either Calculation of Average Power from Recorded Average Voltage, Current, and Power Factor Values With the setting to record average values of voltage, current and power factor, the instrument records the average values of each such input as expressed by the formulas: n U s = 1 Ui [ V ] [ 15 ] n i= 1 n I s = 1 Ii [ A ] [ 16 ] n i= 1 PF s = 1 n n i = 1 PFi [ - ] [ 17 ] Us arithmetic mean effective voltage value within a record interval Ui instantaneous effective voltage value Is arithmetic mean effective current value within a record interval Ii instantaneous effective current value PFs arithmetic mean effective power factor value within a record interval PFi instantaneous effective power factor value n number of measurements taken within a record interval In an additional calculation by the CETIS32 software of active power from such average values recorded is carried out using the formula: P s = U s x I s x PF s = ( 1 n Ui ) x ( 1 n 1 Ii ) x ( n i= 1 n i= 1 21 n n i = 1 Arithmetic mean active power is generally defined as P s = 1 Pi = n i= 1 n n 1 ( Ui Ii PFi) n 1 i = PFi ) [ W ] [ 14 ] [ W ] [ 15 ]

22 It ensues from the above formula that the equations [14] and [15] do not generally yield the same results; the difference increases with rising fluctuation of each U i, I i, PF i value measured. We only receive the same results if the U i, I i, PF i values do not change with a record interval. Arithmetic mean active power calculation from arithmetic mean values of voltage, current and power factor can then only be used for determining informative power value and in the case of not much fluctuation of each of the U i, I i, PF i values within a record interval. To average power it is thus necessary to set the instrument to measure arithmetic mean power in which mode the error described above does not affect the results Temperature Measurement Temperature is measured at the same measurement frequency as of electric quantities. The memory storage features are analogous as well Connection You can connect a thermometer with a 4 20 ma current output to the T model instrument. Power supply for the temperature sensor at around 24 V DC is built in the instrument and the thermometer is energized by measurement current. The thermometer (or current converter) connects to terminals 25 (+) and 26 ( ); polarity has to be observed. A connection example is shown in the appendix. The temperature input circuitry is internally connected to clock synchronization input and communication link circuitry. The length of cable to connect the thermometer is not restricted. The limiting factor is the cable loop impedance which must not exceed about 30 Ohm. A thermometer can be ordered as the instrument s optional accessory Temperature Measurement Setup The range of measurement for a thermometer connected needs to be pre programmed in parameter group 3. Temperature value (in degrees Celsius) at converter current equal to 4 ma (T04) needs to be specified in field L1 and value at current 20 ma (T20) in field L2. The temperature value measured can then be viewed in the shared window of 3PF f T, field L3. temp. at converter current 4 ma temp. at converter current 20 ma L1 L2 SMZ P-03 Re1 Re2 L3 P M Besides manual setup it is possible to set the temperature sensor range using CETIS32 on a Personal Computer. The setup procedure is described in Computer controlled Operation Output Relays The R model features two relays with reverse switching contacts operation of which can be pre programmed (see parameter description further below). 22

23 Connection The relays contacts go to terminals explained in Table 3. They can be loaded with current 4 A at 250 V AC. Table 3: Output relays relay # 1 relay # 2 terminal contact terminal contact 13 operating 16 operating 14 middle 17 middle 15 break 18 break Function The output relay can be used as a single two position switch controller or for indication of a defined condition. The function is illustrated in a graph in Figure 7. Command variable to control the relay s behavior (Rxcv) can be selected as indicated in Table 4. It is further specified how the command variable controls the relay state. There are deviation polarity for relay active state (Rxdp) and relay active state (Rxas) parameters for that. Deviation polarity can be selected as UNDER (UNDE displayed) or OVER ( OVER )and relay active state as ON or OFF. If then, for example, relay 1 should be utilized to indicate exceeded consumption by appliance measured, the relay 1 command variable R1cv is set to three phase active power value P13, deviation polarity R1dp to OVER (to force relay active state when the command variable value is over the preset limit) and relay active state R1as to ON. When the command variable gets over the preset limit, relay 1 will get activated and switches to the on state. Figure 7: Relay function command variable [% nom. v.] hysteresis preset limit + -hysteresis relay state t < t BL t BL relay passive state relay active state t < t BL t BL t < t BL t BL 23

24 command variable Table 4: Relay function command variable summary name name on display nominal value to define limit Rxl% and hysteresis Rxh% single phase voltage U1 / U2 / U3 U1 / U2 / U3 direct measurement: specified - star... Unom [ V ] - delta/aron. Unom x 3 [ V ] single phase voltage U123 U13 measurement via V.T.: any - star... VTp / 3 [ V ] - delta/aron...vtp [ V ] single phase current I1 / I2 / I3 I1 / I2 / I3 ( Pnom / Unom) / 3 [ A ] specified single phase current I123 I13 any singe phase PF PF1/ PF2/ PF3 PF1 / PF2 / PF specified three phase PF 3PF PF13 frequency f F1 limit and hysteresis (phase L1) specified in absolute value [Hz] temperature T T 0 %...T04, 100 %...T20 [ C] single phase active P1 / P2 / P3 P1 / P2 / P3 - single phase quantity: power - specified Pnom / 3 [VA] active power 3P P13-3 phase quantity: three phase Pnom [VA] single phase react. Q1 / Q2 / Q3 Q1 / Q2 / Q3 power - specified reactive power 3Q Q13 three phase single phase app. S1 / S2 / S3 S1 / S2 / S3 power - specified apparent power 3S S13 three phase single phase 1 st harm. PF - specified cos1/ cos2/ cos3 c1 / c2 / c single phase voltage THDU1 / THDU2 / tu1 / TU2 / 100 % THD - specified THDU3 TU3 single phase voltage THDU123 tu13 THD - any single phase current THDI1 / THDI2 / ti1 / TI2 / TI3 100 % THD - specified THDI3 single phase current THD - any THDI123 ti13 The limit (threshold) (Rxl%) is usually specified as percentage of nominal value measured. Nominal values represent 100 % and they are shown in Table 4 ( for Unom see parameter 01). The hysteresis (Rxh%) uses the same dimension and it can specify the relay s zone of insensibility. If the command variable is in the range of values [(Rxl% Rxh%), (Rxl%+Rxh%)], the relay s state does not change. 24

25 Furthermore, the relay s insensibility to fast command variable alterations using block time Rxbl can be set. The relay then only changes its state provided the command variable remains over or under the defined zone (including hysteresis) continuously for at least the preset block time. A relay can also be set to a permanent state by setting the command variable Rxcv to value 0 (permanently off) or 1 (permanently on). Besides these conditions, the relay remains permanently off, independently of the preset command variable value, also if the threshold Rxl% is not specified (condition ----). An exception to threshold value specification is frequency: Rxl% threshold and Rxh% hysteresis are entered in Hertz. When choosing a command variable, it is possible, besides individual single phase voltages, currents and their harmonic distortions, also specify all single phase quantities at a time by selecting an any quantity. The function is explained in the following example: Example: You want to set relay 1 to indicate overvoltage in a three phase outlet. You set command variable R1cv to single phase voltage any, that is U13. You set deviation R1dp to OVER and relay active state R1as to ON. You set threshold, hysteresis and lockout time to values desired. The active relay state, that is closing its middle and operating contacts, takes place if any of the single phase voltages, U1, U2, U3 reaches a value corresponding to the active state. On the opposite, the relay goes to the passive state if none of the voltages corresponds to the active state condition. If, in the above example, there was a requirement to indicate the condition of overvoltage in all three phases at a time, the setting would have to be changed by setting the polarity deviation R1po to UNDER. The relay active state R1as must be then set to OFF or R1as can remain at ON and the relay break contact used for the indication Relay Operation Setup Behavior of either relay can be set completely independently of the other one. The relay 1 function is defined by setting parameter groups 7 and 8, relay 2 function by parameter groups 9 a10. control variable relay active state deviation polarity relay active state L1 L2 L3 SMZ 33 U.13 U.13 OVER ON P P-07 Re1 Re2 M limit hysteresis block time L1 L2 L3 SMZ P P-08 Re1 Re2 M In the above example relay 1 switches on if at least one single phase voltage exceeds the limit = 113 % of nominal voltage (that is with Unom equal to 230 V the value of 260 V) and stays at that level for at least one minute. The relay switches off if for at least one minute all single phase voltages are under the level of = 107 % (that is 246 V). The setting can also be done using a computer see appropriate chapter further below Manual Relay Operation The relay state, controlled by the curve of the command variable selected, can be changed by the operator in a single step. While holding the M button pressed, the instantaneous relay 1 state can be 25

26 switched over by simultaneous pressing button. Analogously relay 2 can be switched over using the button. Immediately after this forced manual change of relay state, however, the selected command variable takes over control of the relay state and puts it (after the preset lockout time has elapsed) back to the relevant state Real Time Circuit Synchronization E model instruments feature a clock synchronization input. This synchronization provides more precise work of the inbuilt real time circuit by an external signal Connection The input is at terminals 19 (+) and 20 ( ). The internal supply voltage of the input is 12 V DC, switching current is 5 ma. Passive contact or transistor connection is assumed. If the signal is generated by a transistor (NPN) or optocoupler, it is necessary to observe the input connection polarity transistor or optocoupler collector to be connected to the + terminal (11), the emitter to terminal (12). Warning!!! The clock synchronization input is galvanically connected with the communication link circuitry (terminal 20 is connected with terminal 30) and with temperature measurement input circuitry. They are isolated from the instrument s other circuitry Function If the clock synchronization function is not set or required synchronization signal is not connected, the inbuilt real time circuit is only controlled by its own crystal oscillator. A connected synchronization signal can synchronize the inbuilt real time circuit by an external clock. The measurement data can then be compared with, for instance, values invoiced by the power supply company. Synchronization of the real time circuit operation has effect on: correct recording of measured electric work in the preset rate zones; correctness of quarter an hour maximum active power value and time stamp recorded; proper reference of the memory record time axis. The synchronization pulse must be at least 100 ms wide. The instrument sets the inbuilt real time circuit (if the function is selected) to the nearest minute at the end of a synchronization pulse. The synchronization pulses can be minutely, quarter an hourly or hourly Clock Synchronization Setup The clock synchronization function can be enabled in parameter sync (window L1), parameter group 12, by selecting ON. If the parameter is set to OFF, no clock synchronization takes place even if sync signal is connected. The setup can also be carried out using a computer (see further below). Warning!!! If the data memory record period is set to less than 1 minute, clock synchronization is not allowed in order to be able to keep time coherency of recorded curves. In such a case the operator is notified of this on attempting to set the sync parameter to the enabled status by an ON I. (meaning ON + exclamation mark) message Pulse Outputs The E model instruments have two pulse outputs. The frequency of generated pulses can be set in dependence on electric work values measured (transmission electricity meter). 26

27 Connection The pulse outputs are implemented using two (galvanically isolated from each other) output NPN transistors at terminals 21 (output 1, +), 22 (output 1, ), 23 (output 2, +), and 24 ( ). Connection of an external recording or control system input optocouplers via a current limiting resistor to these outputs is assumed. The output transistors limit parameters are suited to that: maximum voltage 30 V DC and maximum current 50 ma. If there is a danger of overload, it is convenient to use a fuse 0.3 to 0.5 A. An example connection is shown in the appendix Function The type of electric work to correspond to the frequency of transmitted pulses can be selected between A+ (active power consumed, import), A (active power supplied, export), ArL (reactive power inductive), and ArC (reactive power capacitive). It is further necessary to set the pulse frequency to express the electric work in n/kwh (or n/kvarh). Either output can be set completely independently of the other one. The instrument evaluates electric work measured every five seconds. If an increment of electric power recorded higher than or equal to power corresponding to one pulse is detected, one or more pulses are transmitted. It ensues from the above description that with a relatively high frequency of pulses, it is not necessary to transmit them continuously but in bursts every five seconds. The pulse width is fixed at 100 ms, minimum space between pulses is also 100 ms. Maximum frequency of pulses transmitted is thus 5 Hz Pulse Output Setup The pulse output function needs to be programmed by setting parameter group 14 (see further below). The N1/k pulse density of output 1 can be set in field L1, pulse density N2/k of output 2 in field L2. In field L3 type of corresponding electric work needs to be specified in field L3: for A+ (A+ (active power consumed, import) AI is entered for A (active power supplied, export) AE is entered for ArL (reactive power inductive) RL is entered for ArC (reactive power capacitive) RC is entered The pulse output setup can also be done using a computer (see further below). output 1 pulse frequency / 1kWh output 2 pulse frequency / 1kWh L1 L2 L3 SMZ AI.AE P P-14 Re1 Re2 M electric work type corresponding to output 1 electric work type corresponding to output 2 27

28 3. Computer Controlled Operation Viewing currently measured values and instrument setting can be done not only on the instrument s panel but also using a local or remote computer connected to the instrument via a communication link. Using a computer it is possible to set and view a curve stored in the instrument s inbuilt memory which is not possible on the instrument s panel. 3.1 Communication Links Local Communication Link The instrument s standard feature is a serial communication interface with levels as defined by V.24 (RS 232) and a connector on the front panel. Using this interface instrument parameter setting and data transmission to a portable computer can be carried out. With regard to the fact that the instrument can feature a remote communication interface as well, the communication link in this chapter s description is called local. The interface has a MiniDIN connector on the control panel labeled COM. Signal assignment to pins is shown in Table 5. Table 5: Local communication interface connector configuration signal MiniDIN outlet contact (female) RxD, read data 4 TxD, transmission data 3 /LOCAL, local communication request 5 GND, communication link ground 6 6 outlet (front view) When data are to be transmitted via the local communication link, the operator needs to interconnect the instrument with a Personal Computer using a communication cable (cable listed as optional accessory). The MiniDIN connector of this cable has contacts 5 and 6 short circuited. Plugging in the connector thus causes logical level 0 in /LOCAL signal and the instrument redirects communication to this local interface which is momentarily indicated by a message Loc in the alphanumeric field. At the same time it disconnects from the remote communication link (if installed). For local communication link connection communication parameters within CETIS32 must be set to COM, 9600 Bd and address to 1 (independently of address set in instrument on installation which only is important for main communication link). On unplugging the connector the instrument redirects the communication back to the remote communication link which is momentarily indicated by a message Rem in the alphanumeric field Remote Communication Link An optional feature of this instrument is a remote communication interface via which the instrument can be controlled with a remote computer. From such a computer it is possible to carry out remote instrument setting and current or stored data transmission. The remote communication interface is galvanically isolated from internal circuitry and it can be compliant with RS 232 (instrument model SMZ33 RT/232), RS 485) (... /485) or CAN (... /CAN). One or more instruments can be connected to a remote Personal Computer via such a link. Each instrument must have a different communication address and the same communication rate set. These parameters can be preset using a computer via the local communication link through the activity called Installation in CETIS32 or manually in parameter group 4. 28

29 RS 232 Interface Only one instrument can be connected to this interface. The communication cable length should not be more than a few tens of meters. The instrument can also be connected via this interface using a modem. Then the communication distance and number of connected instruments are not limited. Table 6: RS 232 remote communication interface connector configuration RS 485 Interface terminal signal 27 none 28 RxD 29 TxD 30 GND Up to 32 instruments at a distance maximum 1,200 meters can be connected to this interface. Each instrument must have a different communication address from the range 1 through 253 set within installation. Table 7 : RS 485 remote communication interface connector configuration terminal signal 27 TR 28 DATA A 29 DATA B 30 GND A communication card with a corresponding interface or an external 232/485 level converter connected to a standard serial port must be installed on the computer side. The converter must feature an automatic communication flow direction switching function CAN Interface This is a high rate interface convenient for, for example, transmission of actual measurement data from a large number of instruments up to 110 instruments can be connected to the interface. Communication cable maximum length depends on the communication rate; it is about 500 meters at 100 kilobit per second. Each instrument must have a different communication address in the range 1 through 1023 set within installation. Table 8: CAN remote communication interface connector configuration terminal signal 27 TR 28 CAN H 29 CAN L 30 GND A special CAN interface card must be installed on the Personal Computer side Communication Cable For common applications (cable length up to 100 meters, communication rate up to 9,600 Bd) choosing the right cable is not crucial. It is practically possible to use any shielded cable with two pairs 29

30 of wires (such as MK 4 x 0.15) and to connect the shielding with the Protective Earth wire in a single point. With cable lengths over 100 meters or with communication rates over 20 kilobit per second it is convenient to use a special shielded communication cable with twisted pairs with defined wave impedance, usually around 100 Ohm Terminating Resistors The RS 485 and CAN interfaces require, especially at high communication rates and long distances, impedance termination of the final nodes through installation of terminating resistors. Terminating resistors are only installed at the link s final points (for example one at the Personal Computer and another at the remotest instrument). They are connected between terminals 28 (A or CANH) and 29 (B or CANL). The SMS33 instruments with a remote communication interface have an inbuilt terminating resistor (330 Ω or 120 Ω for RS 485 or CAN) as a standard feature and it is permanently connected between terminals 29 (B or CANL) and 27 (TR). To utilize the terminating resistor, terminals 27 (TR) and 28 (A or CANH) are to be connected Remote Communication Link Protocol KMB Communication Protocol This protocol is used in remote communication via RS 232 or RS 485 when the instrument is connected to a computer through a standard serial communication port (COM). The protocol is preset as default and is indicated as P0 in parameter group No. 4. Data transmission the takes place at communication rate set in the range from 600 to 19,200 Baud (8 bits, no parity, 1 stop bit) Modbus RTU Communication protocol For easy integration into user information systems the Modbus-RTU protocol is implemented too. The protocol can be set asp1n / P1E / P1O ( no parity / even parity / odd parity ). Detailed description of communication protocols implementation will be sent on request Communication via Modem The instruments with an RS 232 interface can be remotely connected via telephone modem. In installation it is necessary to select, besides the communication address, communication rate in accordance with maximum speed of modem used. It is further necessary to select modem communication by setting an initialization string for the modem. Using this string the instrument sets up the modem for it to be able to establish communication and transmit data successfully when called by a remote computer. The modem must be compatible with a basic set of AT commands (Hayes). Practically all modern modems meet this requirement so this communication should not pose any problems. From our practical experience s point of view we can recommend using Microcom modems. The following initialization string has proved suitable with them: ATB0&D0E0&K0&L0Q0V0X1 S0=1 S10=100 If the string does not work with a modem in use, it is necessary to check application of all AT commands in the initialization string following modem documentation and modify the initialization string if required. If there are insisting problems, please contact KMB Systems CAN Communication Protocol An in house communication protocol is implemented description of which exceeds the scope of this manual. For more details please contact. 30

31 3.2 Description of CETIS32 Software for SMZ 33 The CETIS32 software for Windows allows setting all important parameters in an SMZ 33 and archiving these. It further allows recording, visualization and archiving measurement data from this type of instrument. The following chapters describe the procedures for such activities. General principles of work with CETIS32 are described in the CETIS General Description manual Setting Standard Display Ranges The software allows setting a standard display range for each type of instrument. Besides the standard ranges, other information can be set too, especially that concerning report printing. The SMZ 33 is one of the SM-type of instrument so you open the standard view range setup window by selecting Setup Standard Ranges SMx from the menu. This calls the window shown in Figure 8. Figure 8: Standard view ranges In the groups Voltage, Current, Frequency, and Temperature you can set the basic values for scale ranges. When transmitting recorded curves from an instrument to a Personal Computer, CETIS32 sets scale ranges in accordance with these values and saves a graph so created on a disk. If viewing a retrieved graph, the range values remain as original even if they have been changed within the standard range settings. You can further set tolerance zone limits in this window. The zones are used for statistic evaluation in a record report (see Record Report). The Voltage Zone 1 can also be viewed by using the appropriate button and use for visual inspection of measured voltage curves from the point of view of compliance with regulated values. Finally, tariff zone schedule for SM-type instruments can be preset here. The schedule is used when new device with built-in electricity meter is added to object as default tariff zone setting. One of three tariffs 1,2,3 can be set for each hour and electric energy for each tariff zone can be then evaluated separately. The Start of day setting is not important and it is reserved for future use. 31

32 3.2.2 Instrument to Personal Computer Connection via a Local Communication Link It is necessary to set general communication parameters by selecting Setup Communication before the first instrument connection after installing CETIS32. You need to choose the port to be used in local communication (usually COM1), then set the address to 1 and baud rate to 9,600. Correct setting of these general communication parameters is important for loading the device in a CETIS32 database (function Device New Automatic); these communication parameters are always assigned to a new device. After that you connect the device to the computer via a local communication interface (COM connector on the instrument panel) using an appropriate cable. Figure 9: General setting of communication parameters Loading New Device in Database Select the object into which you want to load a new device (object setup procedure is described in the CETIS General Description manual) and then select Item New device Automatic. Figure 10: Loading a new device, device setup window The program identifies a new device type via the local communication link (set to general communication parameters) and it shows the current setting in the Device Setup window (see Figure 10). You press the Save button in this window. This stores the device in CETIS32 database and it is shown in the Devices subfolder of the selected object. 32

33 3.2.4 Device Parameter Setup (Installation) Using the device parameters the character and behavior of input and outputs signals connected to the device are specified. The device parameter setting called Device Installation includes basic parameters and extended parameters Instrument Basic Parameters The instrument s basic parameters are: 1. connection of voltages ( direct connection or via a V.T.) 2. type of connection of voltages and currents (Star, Delta or Aron) 3. nominal voltage value ( for direct connection ) 4. voltage metering transformer ratio (in case of indirectly via a V.T.) 5. current metering transformer ratio 6. transformer nominal power (if applicable) 7. temperature sensor range (if connected) 8. remote communication link parameters (rate, address, optionally protocol) These basic parameters are usually set once for good when connecting the instrument in the grid measurement point or they are only changed occasionally, for example when rebuilding the measurement point or when changing parameters of the main communication link and suchlike. Parameter setting can only be done via the local communication link (LOC). On automatic instrument load (as in previous chapter) record setting as well as current setting of basic and extended parameters called Device Installation are transferred into the CETIS32 database. The installation setting can be viewed by selecting a device using Item Install. Figure 11: Device Installation The device s basic parameter setting is shown in the Device Installation window. If it is required to change the existing basic parameters, it is necessary to set them and then send into the connected device by selecting the Send command. This function sends complete Device Installation to the device, that is besides the basic and extended parameters. It is convenient to save the new setting of basic parameters onto the disk by selecting Save before that. WARNING!!! On sending basic parameters to a device, all data stored in the device s memory are erased and the internal electricity meter reading reset!!! 33

34 Using the Receive button you can download in the device s existing basic parameter setting (for example to check them after sending them to the device or to check the setting if the basic parameters have been changed manually using the device s control panel). On sending or receiving the device s basic parameters, the device s extended parameters described further below are transmitted as well Device Extended Parameters In devices featuring relevant outputs the function of such outputs can be set using extended parameters. The device s extended parameters are stored in window Output Relays, Pulse Outputs and Time Sync Setup window and can be displayed with Outputs button in the Instrument Installation window. They control : 1. output relay behavior 2. pulse output behavior 3. clock synchronization function After pressing this button the parameter setting window is displayed (Figure 12). In the Output Relays group you can set behavior of both relay outputs by selecting command variables, limits, hysteresis and block times. Analogously, in the Pulse Outputs group you can enable pulse outputs by selecting type of electric work and setting output pulse frequency and you can also enable the clock synchronization function. Figure 12: Extended parameters setup After setting a desired function you can send the new setting to the device using the Send button. Extended parameters can be sent to or received from the device separately. This can be utilized if it is necessary to keep the measurement database and or the inbuilt electricity meter reading while changing extended parameters. If you setup the device using the Device Installation window, besides extended parameters also basic parameters are sent to the device thus resetting the database and inbuilt electricity meter. Using the Set button the new setting is remembered and it returns to the Device Installation window. Using the Cancel button the new changes are canceled and the original setting restored. On return to the Device Installation window you can save the extended parameter setting (together with basic parameters) using the Save button Record Setting After installation has been carried out, instrument recording function needs to be set up. This setting defines quantities to be stored in the device s memory and the way of storing them. Record setting can be done via either local or remote communication link. 34

35 In the object window you can view the device setting by double clicking on its icon displayed in the Devices folder. The Device Setup window is displayed. Figure 13: Device setup The window contains the setting which was last saved on the disk. If you want to view the current setting of the device connected, select the Receive Setting action. Parameters that can be changed are organized in a card index s different cards. They can be edited, saved on the disk again or send to the instrument connected General Information It is shown in the General Information card (see Figure 13): device type and serial number object code in which the instrument has been installed record name (such as name of transformer station in object text string) record period memory operation setting maximum record length corresponding to configuration set and instrument memory capacity sampling method comments for curves The name of grid measurement point or transformer can be entered in the Record Name item. This name, together with the time of measurement start, will identify the measurement record in the database on the processing computer s disk. Using the +,, and min/sec buttons you can enter the record interval desired from 5 seconds to 60 minutes. This duration can be set in the appropriate window. The Cyclic Record switch allows choosing a way of treating new data when the instrument s memory is full. If this switch is not in the active position, the instrument stops recording new data on filling up the memory until it is reset. If the switch is in the active position, recording keeps going while new data replace the oldest data. The instrument thus always stores the latest curves of measured quantities in a length proportionate to the memory capacity. Another button can choose an input sampling method from one of the following: 35

36 by setting by voltage extreme by current extreme by cos extreme by maximum single phase active power by maximum three phase active power You can further open a window with notes for the curves in this card ( Figure 14 ). It is possible to make a commenting note of up to 31 characters for each recorded quantity. Using these notes an easier identification of each curve while viewed on the screen or in printed reports is possible. Figure 14: Notes for curves Voltage, Frequency, Temperature You can set the number of records and recording method for the above quantities. In the Voltage group you can set the number of voltage signals required and using the Value stored button you can select a method of recording the measurement values. Figure 15: Voltage, frequency, and temperature setup In the Frequency and Temperature groups you can analogously select aspects of recording these quantities. If the device is for indirect voltage measurement, the voltage metering transformer ratio is displayed informatively. This value can only be changed in Device Installation (see previous chapter). 36

37 In star connection only phase voltages are registered, in delta or Aron connection only line voltages are registered Current, Power In this card you can set measurement and recording of current, power factors and average power in a way analogous to that in the card described above. Figure 16: Current and power setup Using the Average Power Count button you can choose recording of average power. You can choose recording one through three average single phase power curves or one average three phase power curves of the complete outlet. Using the Power Type you can choose whether the average power set will be active, reactive or apparent. With power you can choose whether demand / delivery active power values (or inductive / capacitive reactive power values) will be recorded as separate curves. Further the voltage metering transformer value and transformer nominal power are shown in the card informatively. These values can only be changed when installing the device (see appropriate chapter) Total Harmonic Distortion, Harmonic Components Here you can set recording of harmonic distortion and higher harmonic components selected separately for voltage and current signals. In either case you can choose whether total harmonic distortion and harmonic component values of the first phase or all three phases will be recorded. If you select recording of total harmonic distortion and harmonic components you can further define how the harmonic components are to be recorded. You can choose one of the following methods: when selecting Harmonics Level, levels of higher harmonic components in percent of the fundamental harmonic component will be recorded; each harmonic component to be recorded is selected in the Selected Harmonics group (together for voltage and current) when selecting Maximum Harmonics Orders Spectrum, the orders of the highest level harmonic components ordered by their magnitudes will be recorded (not so their level values); it is also necessary to define how many highest harmonic orders are to be processed in the Number of Harmonic Orders window. 37

38 The total harmonic distortion and harmonic component levels are recorded always as average values over a record interval set. With respect to frequency of evaluation of total harmonic distortion and harmonic components (see appropriate chapter above) it makes sense to set recording of these values at an interval 20 seconds or longer. Figure 17: Total harmonic distortion and harmonic components setup Daily profiles record setting In addition to standard recording function, two more one-day-long records (so-called Daily profiles) of voltages, currents and power factors are possible. Selected profile (S-profile) contains daily record of preset day, Maximum profile (M-profile) contains daily record of the day, when maximum load ( or maximum sum of phase currents ) in measured network occurred. When setting selected profile, Record date in section Selected profile must be specified. Some of future days must be set, otherwise no selected profile will be recorded. Setting is executed with Send record date button. Previous recorded selected profile is cleared at the same time. When setting maximum profile, new checked period is started with Reset button in section Maximum profile (previous recorded maximum profile is cleared at the same time). When pushing Receive actual state button, actual moving averages of each currents and their sum including their time stamps can be checked. 38

39 When complete daily profile (from 00:00 AM do 11:59 PM) is recorded, it can be downloaded to PC and processed in the same way as standard record : After pushing right mouse button over instrument icon you can select Receive profiles item and the profiles will be downloaded to PC. Recorded profiles can be viewed and processed in the same way as standard record. To differentiate standard records from daily profiles, daily profile records in object panel are marked with S-profile or M-profile string Sending Record Setting to Instrument After setting the parameters mentioned above you can send this setting to a connected device using the Send (Setting) button. If you want to keep the configuration setting, it is convenient to save it on the disk using the Save button first. Prior to sending off the setting it is necessary to realize that all data so far recorded in the device will be erased by this step. It is advisable to transmit the last record to the computer before the setting is sent, then (as described further below). After sending the setting the device starts measurement and recording in accordance with the new setting. You can disconnect the communication cable. Record setting does not affect the data displayed on the instrument panel and neither is it possible to change this setting using the instrument panel. It is essential, for correct measurement values recording function, that the internal backup accumulator is charged. It is therefore recommended you leave the instrument with the power connected for at least one week and only then set data recording into the memory as required Recorded Data Transmission to Computer The signal curves recorded in the device memory can be transmitted to a computer via the local or remote communication link. You start data transmission by selecting Receive Data. The curves transmitted are displayed on the screen, saved on the disk and a new item shows in the measurement database. Each record is shown as an icon with the record beginning date, record name and class identification of the device that made the record. 39

40 If you don not make a new setting after transmission, the device continues measuring and recording in accordance with existing setting Use of Measured Curves Each record, stored in an appropriate object in the Records folder, can be displayed by double clicking while having the cursor placed over the record of choice. A graph window will pop up (see CETIS32 General Description). The graph window s main part consists of the graph itself. Curves of quantities selected are displayed in the graph window. Each curve can be selected by curve buttons in the quantity panel and toggle their show / hide status as required. To determine the value of each quantity in a specific point you use the cursor. The cursor is displayed in the graph window on pressing the appropriate button. You can move the cursor using the mouse or, keys. The time shown at the bottom of the graph window gives the cursor current position. The numeric values in the quantity panel show corresponding values of each quantity displayed. The quantities units can be read on the scales on the left and right in the graph window. Figure 18: Graph window displaying measurement record You can tell from each quantity group panel name how that panel s quantities were sampled and recorded. This method is defined by the following indices: avg max min o (t) average value recorded during record interval maximum value within record interval minimum value within record interval instantaneous value at the end of record interval instantaneous value at the moment of slice command variable extreme (see description of sampling quantities) To use the curves displayed there are tools at the top. Their meanings are indicated by the graphic symbols and explained in the CETIS32 General Description manual. 40

41 Record Report Besides graphic representation you can display and print a record report. The report contains the most important statistic data about the measurement in a numeric form. There are minimum, maximum and average values of each phase s voltage over the measurement period, the out of check zone time in percent as set in the Setup standard ranges, information on transformer workload with respect to its nominal current, and so on. In the Total column the average values of each phase s quantities are shown Calculation of Power If the measurement record does not include power, a subsequent calculation of power from the voltage, current and power factor curves measured can be carried out. You can choose calculation of active, reactive or apparent single phase or three phase power. After selecting Graph Power Calculate the Power Calculation window opens; see Figure 19. Figure 19: Calculation of power You check the boxes next to the types of power required. Press the Calculate button. After the calculation has been completed the power calculated shows in the list of measured curves and it can be displayed in the graph including the scale of power units (kw, kvar or kva). If the power is not displayed in the graph, you need to enable their display by selecting Graph Add Panel (if four panels are already displayed, you must remove at least one of them first see CETIS32 General Description manual). When using the power calculated it is necessary, for correct interpretation, to realize from which curves of voltage, current and power factor the power has been calculated (the calculation method is described in a relevant chapter above) Export of Values to DBF file By selecting Graph Export to DBF each value is converted into a numeric form and stored in the DBF format which is easy to import to a spreadsheet for further processing (the power factor and power values are positive for inductive character, negative for capacitive character) Electricity Meter Management The E model instruments have built in four quadrant three phase electricity meter circuitry and they can be, besides standard functions, used an auxiliary electricity meter. If the instrument features the electricity meter, the El. Meter button shows in the Device Setup window. The Electricity Meter window opens on pressing it (Figure 20). The window contains three phase electric work values at three rates and corresponding power factors, quarter an hour maximum power values with time stamp both in each phase and the three phase value, reset time, reading time and tariff zone settings. When the window opens the condition last saved on disk is displayed. Using the Receive button the current information is downloaded to the instrument. The downloaded data contain the current values 41

42 of electric work and quarter an hour maximum power as well as current settings of rate zones. The reading time and reset time are downloaded from the instrument s clock circuit (not from the computer). You can save the condition on the disk (Save button) or print it out (Print button). If you need to change the rate zones, you have to set a new combination and send it to the instrument using the Send Tariff button. Since that moment the electricity meter starts recording in accordance with new rate settings. If you want to reset the electricity meter, use the Reset button. Both electric work counters and quarter an hour maximum power values recorded will be reset. No operations carried out on the electricity meter affect the settings or the course of recording the other data measured by the electricity meter in any ways. Neither does data record setting affect the electricity meter settings in any ways, you only need to take into account that sending the record setting updates the instrument s internal clock circuit whereas the last reset time recorded corresponds to the previous clock circuit setting. Figure 20: Electricity meter 42

43 3.3 RETIS for SMZ 33 General Retis is a computer program developed to monitor the instrument s current condition and archive the measurement data. The software can monitor status of a number of instruments concurrently and it allows setting them up. There are two editions of the program. The basic edition is included in the instrument package on an enclosed compact disk and the latest version can be downloaded via the Internet. This edition has all visualization features in the instrument online mode and allows one-day data archiving. The full edition allows no-limit data archiving as well as operation while the instrument is offline. A demo mode, in which the software can be tested without a connected instrument, is part of the program. The general program operation principles are explained in its helptext. Unless otherwise stated, the features described are contained in the program s both basic and full editions Default Settings The program can save default settings for each class of instruments. A new instrument automatically takes over the default settings in accordance with the instrument s class. The instrument s settings can be edited at any time or restored to the default values. The following groups of default settings can be saved for instruments of the SMZ and SMY classes: panels graphs ranges Open the default settings window by selecting Setup > General Settings > SMZ, SMY in the menu. A window as the one shown in Figure 21 will be displayed. Figure 21 : Default Settings Measuring range is selected automatically in accordance with the current and voltage conversion settings or it can be selected manually in fundamental units Connecting Instrument to Computer and Entering into Database The instrument is to be connected using the appropriate cable to a PC via the local communication interface (COM port) or via the remote communication interface (if available). The instrument is entered into the software s database via the menu Instrument > Add Instrument (Figure 22). 43

44 Figure 22 : Adding Instrument into Database Specify the address and communication port, for example COM1,in the Add Instrument dialog box. Make sure that the communication parameter settings, accessed via Setup > General Settings in the General Settings dialog box, match the instrument s settings. Then communication can be checked by clicking on auto. If communication works correctly, the type of instrument, SMY or SMZ, will show up. The type of instrument can alternatively be selected in the list Instrument Database The instruments entered in the database are shown in a list of instruments (Figure 23). You can do the following in the dialog box: Enable or disable instruments View or hide active instrument View or hide active instrument s floating window Enable or disable data archiving from active instrument View instrument setup and properties dialog box Add or remove instrument Download data from instrument memory if you use full edition of software Figure 23 : List of Instruments 44

45 3.3.4 Instrument Setup Through instrument parameters, specify character and operation of input signals connected to the instrument. There are main parameters and additional parameters. View parameter settings by selecting Settings in the List of Instruments dialog box (Figure 24). Figure 24 : Instrument Settings Main Parameters You can view instrument s main parameters by selecting the Installation card within the Instrument Settings dialog box (Figure 24). The main parameters are as follows: 1. type of voltage (direct or indirect via voltage metering transformer) 2. connection configuration (wye/star, delta, Aaron connection) 3. nominal voltage (if measuring via a voltage metering transformer, this is the transformer s primary voltage value) 4. voltage metering transformer conversion value 5. current metering transformer conversion value 6. transformer s nominal power (if applicable) 7. temperature sensor range (if connected) 8. remote communication line parameters (rate, address, protocol) These main parameters are usually to be set once for good on having connected the instrument to the power system node under measurement or they are occasionally edited, for example after modifications to the system measured or in order to change the principal communication link parameters or suchlike. The program attempts to read data from the instrument on viewing the Instrument Settings dialog box. If this fails, you can read the settings from a file or close the dialog box. The parameters shown in the Installation card can be transferred to the instrument with the Send button or from the instrument with the Receive button. All of the settings (installation, output parameters, recording parameters) can be saved in a single file and retrieved from a file using icons at the bottom left. 45

46 WARNING!!! When you send the main parameters into the instrument, all the data stored in the instrument s memory will be deleted and the instrument s energy meter will be reset!!! Additional Parameters If the instrument features the necessary outputs, such outputs operation can be set up using additional parameters. You can view the additional parameters by selecting Settings in the List of Instruments dialog box s Output Settings card (Figure 25). The additional parameters specify: 1. operation of output relays 2. operation of pulse outputs 3. operation of synchronization feature 4. operation of analog outputs The program attempts to read data from the instrument on viewing the Instrument Settings dialog box. If this fails, you can read the settings from a file or close the dialog box. The parameters shown in the Output Settings card can be transferred to the instrument with the Send button or from the instrument with the Receive button. All of the settings (installation, output parameters, recording parameters) can be saved in a single file and retrieved from a file using icons at the bottom left. When sending additional parameters to the instrument, the instrument data and energy meter values are maintained. Figure 25 : Additional Parameter Settings Recording Parameters In the online mode, Retis receives, displays and subsequently saves all the measurement data from an instrument, independently of the data storage settings in the instrument. The full edition further allows downloading of internal memory data (offline data) and archiving them separately or using them to patch online data, which may be convenient after communication or computer failure. If you want the instrument to record data into its memory, you have to set up the recording parameters. The recording parameters specify the quantities and the way to be recorded. View the recording parameters by selecting Settings in the List of Instruments dialog box s Recording Parameters card (Figure 26). 46

47 The program attempts to read data from the instrument on viewing the Instrument Settings dialog box. If this fails, you can read the settings from a file or close the dialog box. The parameters shown in the Recording Parameters card can be transferred to the instrument with the Send button or from the instrument with the Receive button. All of the settings (installation, output parameters, recording parameters) can be saved in a single file and retrieved from a file using icons at the bottom left. When sending additional parameters to the instrument, all of the instrument data are deleted, but the instrument energy meter values are maintained. Figure 26 : Recording Parameters You can enter the name of a power system node or transformer in the Record Name item. This name is for use within the Cetis program. Recording cycle from 5 seconds to 60 minutes can be specified in the Record Period box. Checking the Immediately checkbox makes the instrument start data recording immediately after the setup is complete, unchecking it causes that recording starts on reaching the record start time. The start time is to be specified in the boxes provided. The Cyclic Record checkbox decides about what happens when the instrument memory gets full. If unchecked, data recording stops until the instrument is set up again. If checked, data recording continues and the new values overwrite the oldest values, so the instrument stores the latest measurement data and the record length corresponds to the instrument memory capacity. One of the following quantity sampling methods can be selected in the following box: on setting on voltage extreme on current extreme on cos extreme on one-phase active power maximum on three-phase active power maximum 47

48 You can specify the number of signals to be recorded in the Voltage, Current, Power Factor, Frequency, and Temperature boxes and select one of the methods of storing the values measured from dropdown menus. If measurement voltage is star-connected, only phase voltage values are stored. If it is delta-connected or Aaron-connected, only line voltage values are stored. You can specify measuring and recording of average power in the Number of Average Power Values. You can select recording of one to three average single-phase power values or average three-phase power of the entire outlet. You can select active, reactive or apparent average power in the Type of Power dropdown menu. You can further specify whether consumption and supply power values, or inductive and capacitive reactive power values, are to be recorded separately. Separate recording of voltage and current signals can be specified in the group of harmonic distortion and selected high-order harmonic components. Both voltage and current harmonic measurements allow recording total harmonic distortion values and signal harmonic components in phase 1 or all three phases. If recording of total harmonic distortion and harmonic components is enabled, you can further specify which harmonic values are to be recorded. You can select one of two methods: If you select Level, high-order harmonic levels will be stored as percentages in relation to the fundamental harmonic component; you check each harmonic component to be recorded using its checkbox (for voltage and current together). If you select Spectrum, the order of the highest-order harmonic components will be stored in the order of their levels (not the levels themselves though); you need to further specify how many highest-order harmonic components (or its orders) are to be processed in the Number of Harmonics box. The total harmonic distortion and harmonic component levels are always recorded as average values over the record period specified. With respect to the frequency of rendering total harmonic distortion and harmonic components (see relevant chapter above), it makes sense to store such values at periods 20 seconds or longer Current Data Operation If an instrument is enabled as active in the List of Instruments dialog box and viewing is selected (see Chapter 3.3.3), the following instrument window will be displayed (Figure 27): Figure 27: Instrument Window 48

49 You can view the measurement data in a table and a graph within the window. You can also view the latest events that took place within the time displayed in the graph. You can view archive data in a similar fashion. More details are in the program s helptext Energy Meter Operation Instruments with the E option include circuitry of a four-quadrant three-phase energy meter, so besides standard features the instrument can also be used as a secondary energy meter. If an instrument has the E option, the item Setup > Energy Meter appears in the menu. The Energy Meter window (Figure 28) will be displayed on selecting this menu item. The window contains three-phase energy values at three metering rates and corresponding power factors, quarter-an-hour power maximum values with timestamps both in each phase and the threephase value, the reset timestamp, time of reading, and metering rate settings. The status last saved on disk will be displayed on opening the window. Current information is transferred from the instrument on pressing the Receive Status button. The data received contain the new energy values and quarter-an-hour power maximum values as well as current settings of metering rates. The time of reading and reset timestamp are taken from the instrument s clock circuit (not from the computer clock). If metering rate settings need changing, you have to specify the new settings and send them to the instrument using the Send Rates button. Since that moment, the energy meter starts recording at the new metering rate settings. If you want to reset the energy meter, use the Reset button. This resets the energy counters and quarter-an-hour power maximum values recorded. Energy meter operations do not in any ways affect settings or recording of other data measured by the instrument. Analogically the data recording parameters do not in any ways affect the energy meter settings, you only need to keep in mind that when you send recording parameters to the instrument, the instrument clock circuit gets updated while the last reset timestamp recorded corresponds to the previous clock circuit setting. Figure 28 : Energy Meter If an instrument is enabled as active and recording is enabled in the List of Instruments dialog box (see Chapter 3.3.3), Retis saves energy meter values to an archive file at fifteen-minute intervals. These values can be viewed by selecting Setup > Energy Meter in the menu for the appropriate archive data displayed. 49

50 3.4 Instrument Computer Control Problems, Possible Causes and Troubleshooting Problem: While setting the device or downloading data to the Personal Computer, the program shows a message Device Does Not Respond: with communication via the local link, check communication cable for correct connection (the instrument must display Loc on plugging in the cable), further check communication parameter settings in the program (setting of appropriate COM port, communication arte at 9600 Bd, address 1) with communication via the remote link, check communication cable or communication converter for correct connection, further check communication parameter settings in the program (communication rate, address) and in the device (manually in the parameter group 4 settings or using a computer via the local link in Device Installation) Problem: while downloading data from the instrument to a Personal Computer the program shows a message Memory Error xx, Retry Device Setup : setup the device and make a test (short time) record if the error insists, the instrument needs repairing by the manufacturer if the device has been disconnected from the power for an extended period of time, leave it connected to power supply for a few days (to charge the backup accumulator) and then make the short time test record mentioned above Problem: while downloading data from the device to a Personal Computer the program shows a message No New Records in Device : when setting up the device, data recording from a point in time was set which has not occurred yet (you can check this by downloading device settings) Problem: The graph of power factor, total harmonic distortion or harmonic components contains some PWOff values although neither voltage nor current values are PWOff as well: the values of current or voltage are too low so the quantity at issue can not be measured by the device 50

51 4. MAINTANENCE, SERVICE Maintenance The SMZ 33 instruments do not require any maintenance in their operation. For reliable operation it is only necessary to meet operating conditions specified and not expose the instrument to violent handling and activity of water or chemicals which could cause mechanical damage. The instrument has a T0.16L (230 V AC supply voltage type) a T0.32L (115 V AC supply voltage type) mains fuse to disconnect it on incorrect power supply voltage connection or on a breakdown. The fuse is not accessible for a user, the instrument needs to be sent to the dealer that will arrange its replacement. The built in VL2020 lithium accumulator can backup the memory and real time circuit for about 30 days without power supply when fully charged, at average temperature 20 C and load current in the instrument less than 10 µa. With respect to the fact the instrument is designed for nonstop operation and the backup feature is there only to cover power failures, this capacity is sufficient. When the power is present, the accumulator is being charged. If the accumulator is completely flat, it will reach the fully charged condition in about 60 days from being connected to power. If the operating mode of the instrument is such that power failure time is long, it is, for proper backup function, necessary that the ratio of the power on time to the power off time be at least 2 to 1 and the maximum power off time not exceed 30 days. The accumulator s service time depends on operating conditions (especially operating temperature, number of charging cycles and charging depth), it should, however, typically be the design life of the instrument (about 10 years). If there is an accumulator defect, it is necessary to ship the instrument to the manufacturer for battery replacement or it can be replaced by the manufacturer s specialist on the spot. Note: a special design instrument can feature a lithium cell instead of an accumulator which can provide backup for about 8 years without power supply. Warning!!! If you replace the accumulator by yourself, you must not install a classic lithium battery that must not be charged!!! Violating this warning will cause an explosion of such a battery with all possible consequences!!! Service If the product has a breakdown, you need to complain to the supplier at their address: Supplier : Manufacturer :, s.r.o. Dr. M. Horákové LIBEREC 7 Czech Republic telephone fax e mail : kmb@kmb.cz website : The product must be in proper package to prevent damage in transit. Description of the problem or its symptoms must be delivered together with the product. If a warranty repair is claimed, the warranty certificate must be sent in. In case of an out of warranty repair you must enclose an order for the repair. 51

52 5. TECHNICAL SPECIFICATIONS measured quantities voltage V eff (+/-1 % +/-0,5V) current ( I nom = 5 A eff ) 0,01 6 A eff (+/-1 % +/-0,01A) permanent overload (IEC 258) voltage 800 V eff, current 10 A eff frequency Hz (0.2 %) power factor (PF, cos fi) (+/-2 %, for current load 10 % plus) harmonic components / total harmonic distortion power (active/reactive/apparent) from 25th order, % / % (+/-10 %, for U value or from 10 % up of measurement range) 0 10 kw/kvar/kva (+/-2 %, from current load 10 % up) electric work (active, reactive) ,999,999 kwh (+/-2 %) temperature as converter range used (temperature/current 4 20mA ) (1 %) other parameters voltage input impedance current input serial impedance power supply relay output (2x) > 1 MΩ < 10 mω 230 V / Hz (+15 / -20 %), max. 10 VA switching contacts 230V AC / 4A pulse output (2x) optically isolated (from each other too), max. 30V DC / 50 ma, minimum pulse/space length 100 ms clock synchronization input optically isolated, 12V DC / 20 ma, minimum pulse length 100 ms, minute or quarter an hour signal operating environment class C1 in compliance with IEC operating temperature 25 to 50 C operating humidity 5 to 100 % storage temperature 40 to 70 C installation overvoltage category III in compliance with EN EMC emission in compliance with EN 55011, class A, EN 55022, class A EMC immunity in compliance with EN , EN , EN , EN , EN EMC emission & immunity in compliance with EN measurement cycle record interval memory record of value measured remote communication interface about 3 seconds 5 seconds 60 minutes maximum 1024 kb time, date, minimum, maximum, average, sample RS 232 or RS 485 or CAN, KMB or Modbus-RTU protocol 52

53 design case plastic box DIN display LED, 3 x 4 seven segment digits + 4 matrix characters protection IP 4x, back panel IP 2x dimensions 144 x 144 mm, built depth 80 mm panel cutout 138 x 138 mm, tolerance 0/+1 mm mass about 1.5 kg 53

54 6. Example Connections 54

55 55

56 56

57 57

58 RS-232 interface converter RS