C 2030 חפר מיכשור ומערכות בע"מ טכנולוגיות לטיפול במים ושפכים מיכשור אנליטי למדידה ובקרת תהליכים OPERATOR'S MANUAL. 2- Wire E.C transmitter Din Rail

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1 HEFER SYSTEMS & CONTROLS LTD. Water & Waste Water treatment Tech. Process Analytical Equipment HEFER חפר מיכשור ומערכות בע"מ טכנולוגיות לטיפול במים ושפכים מיכשור אנליטי למדידה ובקרת תהליכים OPERATOR'S MANUAL C Wire E.C transmitter Din Rail POB 8016, Netanya 42504, Israel Tel: Fax: Web: sales@hefer.co.

2 GENERAL This manual applies to the C 2030 digital 2-wire transmitter DIN RAIL housing. It explains the purpose of the equipment, describes the components of the system and the procedures for installing, operating and calibrating the equipment. Some maintenance suggestions are also provided. FUNCTIONAL DESCRIPTION This transmitter, when connected to the E.C. cell provides a digital readout of the Conductivity of aqueous solutions. The transmitter will perform manual or automatic Temperature compensation to correct Conductivity readings for Temperature related variations. Temperature information is displayed by pushing button "2" marked "TEMP". Measuring scales, operating Frequency and decimal point are selectable. The transmitter provides an isolated 4/20 ma output, proportional to the Conductivity value which is suitable for data acquisition systems, recorders, controllers or other input devices that require a 4/20 ma input. The front panel contains trimmer pots for Zero and Cell constant adjustment. Zero is adjusted by trimmer "3" marked "zero" and Cell constant is adjusted by trimmer "4" marked "sens". PHYSICAL DESCRIPTION The transmitter enclosure is designed for DIN Rail mounting. It consists of a plastic case with front panel which is coated by a polycarbonate membrane (Fig. 1), to ensure maximum anticorrosion characteristics. For field applications, mounting in a splash proof or weather resistant box is suggested. Figure 3 describes the physical details and dimensional characteristics. Connections to power supply, loads, recorder, RTD, electrodes and probe are installed on to the terminal block connector

3 SPECIFICATIONS Display: Input: 2-electrodes E.C. cell Output: Scales: Temp. Compensation: Temp. Comp. Coefficient: LCD 4-electrodes E.C. cell RTD Pt100, 2 or 3 wires 4/20 ma isolated 0/200.0 µs - 0/2000 µs, 0/20.00 ms -10.0/120.0 C manual or automatic 0/4.0 %/ C adjustable Temp. Comp. Reference: 20 C Zero: adjustable +/- 15 % Slope: adjustable 86/112 % narrow range adjustable 0/160 % wide range Operating Temperature: 0/50 C Operating Humidity: Power supply: Isolation: Terminal block: Net Weight: Dimensions: Mounting: 95 % without condensation 10/30 VDC 500 Volt Input to Output detachable 200 gr. 105 x 95 x 58 mm (6 modules) DIN Rail mountable - 3 -

4 PHYSICAL INSTALLATION The transmitter must be installed into an enclosure for outdoor or indoor use and may be located close to the measuring point or some distance away in a control area. The transmitter's housing is designed for DIN Rail mounting. The Conductivity cell must be mounted properly if the system is to operate accurately and efficiently. It must meet the following requirements: - the sample in the cell must be representative of the whole solution - the solution must circulate continuously through the cell - the flow velocity in the cell must not be so high as to cause cavitation. - the position and orientation of the cell must not trap air-bubbles near the electrode area - sediments must not accumulate within the electrode area - in all dip cell installations the water must be continuously agitated. Keep the cable away from power wires on the overall length. This cable too must not be interrupted on overall length. If interruption is necessary, the extension cable must be fastened to the high insulation terminal strip. The cell's cable must be protected by a sheath and not installed near power cables. Interrupting cables must be avoided or carried out using high insulation terminals. ELECTRICAL INSTALLATION The electrical installation consists of: (see Fig. 2) - connecting the power supply to the transmitter - connecting the cell or the probe to the transmitter - connecting the Temperature sensor All connections within the transmitter are made on the terminal block. connecting the power - connect dc power " + " to terminal "1" marked " + " - connect the terminal marked " - " to terminal " + " of the load - connect dc power " - " to terminal " - " of the load The unit is protected against eventual inverted connections - 4 -

5 WARNING Verify the supply Voltage prior to connection to the transmitter. Connecting the 2-electrodes cell (probe) Cell cabling is a critical component for trouble free system operation. - use the original cable on overall length between sensor and input terminals of the transmitter. - Extension cables should be avoided. When necessary, always use only high insulation terminals. - avoid installing cable near any power cables. - connect the cell cable to the terminals "10-13" (marked " CO - CI ") Connecting the 4-electrodes cell This special cell must be connected to terminals " ". See the specific instruction manual for this E.C. sensor. Connecting the Temperature sensor The model C 2030 features Automatic Temperature Compensation carried out by means of a RTD Pt100. The Temperature sensor has to be installed in the same solution being measured, close to the E.C. cell in-line or in the tank. ATTENTION In order to activate the ATC function, prior to connecting the RTD between terminal "4-5-6" marked "T1-T2-T3", it is necessary to remove the jumpers from terminals "3-4" and "5-6". These jumpers must be reinstalled when operating the transmitter in manual temperature mode. The RTD connection as above described will also provide a digital display of temperature values. The sample Temperature value is displayed by pushing the Key pad "2" marked "TEMP" on the front panel. The Temperature readout will not disrupt the measuring functions of the transmitter

6 SYSTEM CHECK Before connecting the system to the power supply: - check that all connections are installed correctly - check that all cables are properly fastened to prevent strain on the connections - check that all terminal-strip connections are mechanically and electrically solid OPERATING THE SYSTEM Pre-operation check The system's controls and indicators are all located on the front panel. The transmitter LCD will be displayed to indicate that the unit is on. Push the Key pad "2" to check the sample Temperature (if RTD is connected), or the Manual Temperature value (RTD not connected and jumpers installed). Push the button "S1" and adjust the Temperature Coefficient value on the display by means of the trimmer "R33" marked "TC". (see Fig. 2) (Standard value is 2.0 %/ C) Scales selection Select the scale as per following table by the dip-switches S2 marked A and S3 marked B: Scale Switch S2 Switch S µs OFF OFF 2000 µs ON OFF ms OFF ON - 6 -

7 Frequency selection Select the frequency as per following table by the dip-switches S4 marked M and S5 marked H: Frequency switch S4 switch S5 Low OFF OFF Medium ON OFF High OFF ON Select low frequency for µs scale Select medium frequency for 2000 µs scale Select high frequency for ms scale Decimal point selection Select the decimal point as per following table by the dip-switch S6 marked 1, S7 marked 2 and S8 marked 3: Decimal point Switch S6 Switch S7 Switch S8 XXXX OFF OFF OFF X.XXX ON OFF OFF XX.XX OFF ON OFF XXX.X OFF OFF ON The circuit boards of the unit are pre-adjusted at the factory. If sensors and probes have been installed correctly as previously described, the system should operate correctly requiring only the K cell calibration. WARNING: improper wiring connections which result in damage to the transmitter are not covered under warranty

8 Electrical calibration The following procedures can be used to verify that the system is operating satisfactorily, and it can be repeated periodically to check that the transmitter is maintaining electrical calibration: - connect a Conductivity simulator to terminals " 10-13" - simulate Conductivity values over the entire scale - adjust "zero" and "slope" with trimmers located on the front panel For the customer's convenience it follows the equivalence table between the Electric Resistance (Ohm) and the Electric Conductivity (Siemens) according to the relation: 1 1 Siemens = Ohm R ohm 1 Mohm 100 Kohm 10 Kohm 1 Kohm 100 ohm 10 ohm C Siemens 1 micros 10 micros 100 micros 1000 micros 10 ms 100 ms NORMAL OPERATION As solution passes the installed E.C. cell, the display will indicate instantly the E. Conductivity value of the solution currently being measured. Manual Temperature Compensation The manual Temperature compensation is available when the RTD Pt100 is not installed. - Install the jumpers between "3-4" and "5-6". - Push the Key pad "2" on the front panel (fig. 1) and adjust the trimmer "R5" marked "T MAN" (fig. 2) to indicate the desired Temperature value on the display

9 Cell constant adaptation If the cell constant value is not exactly K = 1.00 (see the value marked on the cell) the meter must be calibrated in order to adapt the meter to the cell. The calibration is obtained by means of S.C.S. (Standard Conductivity Solution), adjusting the sensitivity trimmer marked "sens". If necessary adjust the coarse sensitivity trimmer "R34" marked "SENS ADJ". Chemical calibration of the Conductivity When the cell constant is unknown or is to be checked, it is suggested the following calibration procedure by means of Conductivity Standard Solutions: - prepare a standard KCl solution (see tables) - operate the meter as for when measuring non Temperature-compensated - immerse the cell into solution and adjust the fine sensitivity trimmer or the coarse sensitivity trimmer if necessary - The accuracy of the calibration depends on the purity of the water and the purity of the dissolved salt STANDARD CONDUCTIVITY SOLUTIONS KCL concentration 1 N 0.1 N 0.01 N Temperature C 0 C C C C C C C C C C C C C C C XXXXX 27 C XXXXX 28 C XXXXX XXXXX 29 C XXXXX XXXXX 30 C XXXXX XXXXX KCl normal solution: Prepare by dissolving gms. of Research Grade Potassium Chloride in 1 liter of distilled water Note: Values in millisiemens (millimhos/cm.). Low Conductivity standard solutions are not steady

10 PREVENTIVE MAINTENANCE Transmitter Quality components have been used to ensure a high level of reliability. Frequency of maintenance or recalibration is variable based on each particular application. As with any electronic device, the mechanical components, such as potentiometers and connectors, are the most probable sources of potential problems. - Check for damage of the electrolytic capacitors if the meter is exposed to temperatures above 60 C - check for damage in all the electronic components if the meter is subjected to excessive voltage or power surges - Check for damage of the electronic and mechanical components if the meter is dropped - repeat the pre-operation check periodically to ensure proper operation - check that all the connections are free from moisture and contamination such as rust and corrosion WARNING: Disconnect the power supply to the monitor before performing the following procedures: - Inspect the printed circuit boards for dirt and corrosion; clean as necessary and blow dry. - Tighten all the terminal-board connections and mounting hardware. - Replace the front panel circuit board or the base circuit board. Sensor Coatings on the Conductivity cells measuring surface can affect operation. Solutions which are high in alkaline content and or solutions which contain slurries, oils, grease etc., will require regular cleaning and inspection of the cell's measuring surface

11 TROUBLESHOOTING GUIDE Symptoms Probable cause Action LCD not displayed reading meter Power source problem; incorrect power wiring check power supply check wiring clean sensor Display reading too high/low Display reading does not change Slope will not adjust cell failure; meter uncalibrated cell damage; short circuit Cell damage; open Temp. circuit Calibrate with S.C.S. sensor replacement check cable sensor replacement check ATC sensor/jumpers