Instruction manual 862 MIR Multiple temperature selector with MPU, HPU or OPU board

Transcription

1 Instruction manual 862 MIR Multiple temperature selector with MPU, HPU or OPU board ovember 2005 Part no.: _Rev2 Enraf BV PO Box AV elft etherlands Tel. : Fax : info@enraf.nl Website : Instruction manual 862 MIR Page

2 Preface Preface This manual has been written for technicians involved in the installation, commissioning and service of the Enraf 862 multiple temperature selector unit (MIR) connected to Enraf series 854 level gauges, 877 FI or 873 SmartRadar. For installation of the 862 MIR and the 863 MRT (Multiple Resistance Thermometer), refer to the installation guides of these instruments. For an overview refer to the list of related documents in appendix A. A description preceding the procedures gives the technical information necessary to understand its functioning. It is recommended to read this description prior to performing any of the procedures. Safety and prevention of damage Safe execution of the procedures in this manual requires technical experience in handling tools, and knowledge of safety regulations of electrical installation in hazardous environments. "Warnings", "Cautions", and "otes" have been used throughout this manual to bring special matters to the immediate attention of the reader. A Warning concerns danger to the safety of the technician or user; A Caution draws attention to an action which may damage the equipment; A ote points out a statement deserving more emphasis than the general text, but does not deserve a "Warning" or a "Caution". The sequence of steps in a procedure may also be important from the point of view of safety and prevention of damage; it is therefore advised not to change the sequence of procedural steps or alter a procedure. Legal aspects The information in this manual is copyright property of Enraf BV, etherlands. Enraf BV disclaims any responsibility for personal injury or damage to equipment caused by: eviation from any of the prescribed procedures; Execution of activities that are not prescribed; egligence of the general safety precautions for handling tools, use of electricity and microwave radiation. EC declaration of conformity This instrument is in conformity with the protection requirements of EC Council irective 89/336/EEC. The CE conformity marking fulfills the provisions of E Generic Emission Standard E Generic Immunity Standard when installed, maintained and applied according to requirements as specified in this manual. Additional information Please do not hesitate to contact Enraf or its representative if you require additional information. Page 2

3 Table of contents Table of contents Preface... 2 Introduction General Operating principle Measuring sequence Commissioning Format critical items Temperature related settings Additional settings for an 877 FI ata items Error codes Temperature error MPU/HPU/OPU (item EM) Temperature status request (item MQ) Specifications Mechanical Electrical Cabling Safety Accuracy Environmental... 5 Item description... 2 Appendix A Related documents... 9 Appendix B ASCII table Instruction manual 862 MIR Page 3

4 Introduction Introduction. General The 862 MIR temperature selector is used for interfacing an 863 Multiple Resistance Thermometer (MRT). This unit is basically a solid state electronic element selector, containing all hardware necessary for selecting and measuring an MRT with up to 2 temperature elements with one or two spot elements. The 862 must always be used in combination with an 854 level gauge, 873 SmartRadar or an 877 Field isplay and Interface. These instruments must be equipped with an MPU, HPU or OPU option board to interface the 862 MIR..2 Operating principle Since most liquids, stored in storage tanks, are not homogeneous in temperature, an average temperature measurement over the entire liquid column is required. A Multiple Resistance Thermometer can provide this true average temperature measurement. An MRT comprises a number of resistance elements of different lengths, all starting near the tank bottom. To measure the average product temperature, the longest fully immersed element is automatically selected and its temperature measured. The average gas temperature is calculated by measuring the temperature of the longest resistance thermometer element and subtracting the contribution of the average product temperature. When the MRT is equipped with a spot element in the upper part of the MRT, or there is a separate gas spot element, then the gas temperature is measured directly. The optional board, located in the 854 level gauge, 873 SmartRadar or 877 FI, selects the longest immersed element for the average product temperature calculation. The XPU processor in these instruments converts the average temperature into a serial Bi-Phase Mark modulated signal which is transmitted via the 2-wire Enraf field bus to the supervisory system. Intrinsic safety is obtained by applying full galvanic isolation of the primary connections and the remainder of the circuitry. The measurement current for the resistance thermometers is ma. Selection of each appropriate resistance element is obtained by solid state switches. In order to warrant a maximum integrity and accuracy of the measurement values, a number of measurements is taken, such as: automatic offset compensation linearity testing gain calibration To enable these corrections, a high stable and precise reference and test resistor (0.005% and 3ppm/ C) are incorporated. All measurements and corrections are performed continuously. All measured data retrieved from the convertor is accompanied by status information and a BCC (Block Check Character). Page 4

5 Introduction.3 Measuring sequence The measuring cycle of the 862 MIR takes approximately 37 seconds. In that time the following data is measured (see table). Cycle Measurement R ref 2 4 R R3 5 R gnd 6 R test Each resistance measurement is measured with ma current and without current. The measurement without current is an offset measurement. In measurement cycle a conversion factor is determined: Hz/ohm. With this conversion factor all other resistance measurements are calculated. Figure. Measuring principle This conversion factor is determined with every measurement (37 seconds). In this way an auto calibration of the 862 MIR is obtained. Instruction manual 862 MIR Page 5

6 Commissioning 2 Commissioning The commissioning of the optional MPU, HPU or OPU board should be performed after the basic commissioning of the level gauge, radar gauge or indicator. The items mentioned in this section resides under protection level Format critical items When the temperature dimension and/or the decimal separator has to be changed, it should be done at the start of the commissioning. Item ame escription T Temperature dimension One ASCII character; either C or F. C : degrees Centigrade F : degrees Fahrenheit Both dimensions have the same format: sign XXX sep XX. where: sign : + or - X : digit sep : decimal separator (. or, ) P ecimal separator One ASCII character; either. (point) or, (comma). If the instrument is equipped with an XPU 2 board, all related items are automatically converted. With an XPU board, all items depending on the temperature, level, density and pressure format have to be re-programmed with the correct decimal separator. 2.2 Temperature related settings Item ame escription MT Element type Three ASCII characters (C3 C2 C). Selects the element type connected to the 862 MIR. C3: R refers to an MRT without spot element Q refers to an MRT with spot element refers to an MRT with spot element and separate gas spot element E refers to an MRT without spot element and separate gas spot element C2 C: SA Sangamo MRT ( C) SS Sangamo spot ( C) BE Beacon MRT ( C) BS Beacon spot ( C) PL Pt00 large range ( C) PS Pt00 small range ( C) I i9 ( C) CB Cu90 Beacon MRT ( C) C Cu90 ulectron MRT ( C) CS Cu90 spot ( C) For dual spot element configuration, select item MT as XX or EXX and item M set to 0 (XX: selection from C2 C). Page 6

7 Commissioning Item ame escription M umber of elements Two ASCII digits. This item specifies the number of elements from the MRT, inclusive the spot element. The maximum number of elements is 3. MR Reference resistor Internal floating point format. For the 862 MIR, the reference resistance must be set to: E+03 (277.5 ohm). Refer to figure 2. MO Temperature element offset Format according to item L. The offset represents the distance from the tank zero level to the lowest position of the MRT. ote: Incase of ullage measurement, distance MO is taken from the upper reference point. Figure 2. MRT definitions Instruction manual 862 MIR Page 7

8 Commissioning Item ame escription MI Switch hysteresis Format according to item L. The distance MI is a hysteresis around the switching point of the temperature elements. MP Product immersion depth Format according to item L. The distance MP specifies the minimum required liquid level above a element before it is selected for the average product temperature calculation. MG Gas immersion depth Format according to item L. The distance MG specifies the minimum required distance before the resistance value of the longest element is taken in the average gas temperature calculation. TU Temperature status conversion One ASCII character. efault this item is set to T. If necessary, this item can be set to an other character. 2.3 Additional settings for an 877 FI Item ame escription OB Option board Three ASCII characters. This item informs the XPU what option board is installed. That can be: MPU (for MPU option board) HPU (for HPU and OPU option board) EG Enable temp. transmission One ASCII character; either or E. With this item can be selected if the 877 FI shall answer on a temperature request (C-record), addressed to the connected level gauge. E : transmission of temperature record enabled : transmission of temperature record disabled TF Temperature source selection One ASCII character; either I or E. This item selects if there is a temperature measurement inside the indicator (Internal) or to be fetched from the Enraf field bus (External). This concludes the commissioning of the 862 MIR temperature items. I : Internal (MPU, HPU or OPU option board installed) E : External Page 8

9 Commissioning 2.4 ata items There are of number of data items for the measured temperature, checks and status information. These data items are: Item ame escription AP Average product temperature This item contains the average product temperature, calculated from the longest immersed element. It is preceded by four status bytes from item MQ. AG Average gas temperature This item contains the average gas temperature, calculated from the longest element reduced with the average product temperature influence. It is preceded by four status bytes from item MQ. MQ Temperature status request This item contains four bytes with temperature status information. For description of the status, refer to chapter 3.2. MU Test resistance The measured test resistance in floating point format. The value should be: 370 ohm ± 0.03%. U0 UC Calculated element positions Format according to item L. These items gives the position of each element with respect to the lowest part of the MRT. U0 : st position of element (0.25 m or 0.65 m) U : nd position of 2 element (0.65 m or.25 m) UC : th position of 3 element (22.95 m or m) V0 VF Element temperatures Format according to item T. These thirteen items contains the temperature of each element. V0 : st temperature of element V : nd temperature of 2 element VC : th temperature of 3 element VV Temperature pointer value Internal floating point format. Refer to the item description of items VV and VP in chapter 5. v w, x y Selected value 0 0, Element resistance R R 0, 0 0 f_ Rref 0, 0 f_offset_ Rref 0, 0 2 R_ cable 0, 0 3 Element being measured 3 YP Stored average prod. temp. Format according to item T. Stored product temperature, copied from item AP, after an ST command was given. Instruction manual 862 MIR Page 9

10 Error codes 3 Error codes 3. Temperature error MPU/HPU/OPU (item EM) This item contains the most recent temperature error encountered by the MPU, HPU or OPU board. Error codes 22xx are from the MPU board, 24xx are from the HPU board and 26xx are from the OPU board. 2x00 o error, value at initialization 2x68 Overflow bit set in transmitted data. Check element 2x50 Element detected absent wiring connections 2x5 Element 2 detected absent 2x69 CRC error in transmitted data ) 2x52 Element 3 detected absent 2x75 General MIR error (R_ref and / or R_gnd failed) 2x53 Element 4 detected absent 2x78 Item MR not set to any value 2x54 Element 5 detected absent 2x80 Ratio R_test / R_ref invalid (should be 0.75) 2x55 Element 6 detected absent 2x85 egative element resistance. MRT element wrongly 2x56 Element 7 detected absent connected or absent 2x57 Element 8 detected absent 2x90 Floating point calculation failure (on processor board) 2x58 Element 9 detected absent 2x92 o communication with MIR during last 0 seconds. 2x59 Element 0 detected absent Check cabling between 862 MIR and connected 2x60 Element detected absent instrument 2x6 Element 2 detected absent 2x93 Check the not connected element terminals. All not 2x62 Element 3 detected absent connected terminals must be connected to ground 2x67 Wrong sequence number in transmitted data; (terminal C4-6) 862 MIT will be reset ) 2x94 Cable resistance too high. Check the two black leads of the MRT ) Communication error with 862 MIR; check wiring and 2x95 Wrong type of element selected. Check item MT grounding between 862 MIR and connected instrument 3.2 Temperature status request (item MQ) Four bytes status information (B0 B B2 B3) with the following meaning: Status byte 0: Contains the characters 0 C, indicating the highest immersed element of the MRT. At start up this is: I. Status byte : Status byte 2: bit 0 : General temperature fail bit 0 : Last valid level used : Fail in average product temperature : Manual level used 2 : Fail in average gas temperature 2 : Level time out 3 : Level exceeds lowest element 3 : 0 4 : Level exceeds highest element 4 : 0 5 : Element fail (one or more elements defect) 5 : Out of specified temperature range 6 : 6 : 7 : 0 7 : 0 Status byte 3: For decoding of the status bytes, refer to the bit 0 : o previous store command ASCII table in appendix A. : Alternative (lower) element selected 2 5 : 0 6 : 7 : 0 Page 0

11 Specifications 4 Specifications 4. Mechanical imensions height: 60 mm, width: 60 mm, depth: 90 mm (6 / 6" x 6 / 6" x 3 / 6") Material aluminium Mechanical protection IP65 Weight 2.2 kg (5 lbs) Mounting on top of the / 2" BSP threaded extension tube of MTT sensor Optional rail or wall mounting 4.2 Electrical Power supply the power supply is obtained by the 2 wire communication line from the optional MPU, HPU or OPU board in the 854 level gauge, 877 FI or 873 SmartRadar. 4.3 Cabling Cabling MIT to level gauge one twisted and shielded pair, R max = 25 ohm. Or indicator For the maximum values of the capacitance and inductance, refer to the appropriate approval certificate. Cable entries to associated instrument: standard PG6; 3 with reducer to / " PT or M20 x.5 4 to 864 MTT; 3 3 / " BSP (standard), or / " PT (on rail) or / " PSM or PG Safety Temperature connections intrinsically safe according to CEELEC E EEx ib IIB T4 for connection to MPU, HPU or OPU option board (terminals C6,2) intrinsically safe according to CEELEC E EEx ia IIB T4 for connection to 864 MTT (terminals C C5) Ex-ia for Class I, ivision, Groups C, when connected to MPU, HPU or OPU optional board (Factory Mutual) Ex-ia for Class I, ivision, Groups C, when connected to MPU optional board (CSA) 4.5 Accuracy Combination 862 MIR and 863 MRT ±0.2 C (±0.35 F) for temp. range: -20 C to +00 C (-4 F to 20 F) ±0.45 C (±0.8 F) for temp. range: -50 C to +200 C (-60 F to 390 F) 4.6 Environmental Ambient temperature Storage temperature -40 C to +85 C (-40 F to +80 F) -50 C to +85 C (-58 F to +80 F) Instruction manual 862 MIR Page

12 Item description 5 Item description All items, related to the temperature measurement with the 863 MRT / 862 MIR, connected to the optional MPU, HPU or OPU board are described in this chapter. The items can be of the type (ovram), (data) or C (command). ovram items are stored in the OVRAM on the XPU board of the instrument (for instance: element type, item MT). ata items contains measured and calculated data or error codes (for instance: average product temperature, item AP). ata items are not stored in the OVRAM and are lost after a reset or power down. Command items result in an action (there is only one command: store, item ST). The protection level refers to the protection level or 2 password which is required to issue them. Item: AG Average gas temperature Protection: imension: efault value: no write access determined by item T IF@@ The average gas temperature is obtained by computing the resistance of the non-immersed part, minus length of item MG, from the longest element. For the description of the 4 status bytes, refer to item MQ (chapter 3.2). Item: AP Average product temperature Protection: imension: efault value: no write access determined by item T IF@@ The average product temperature is calculated from the resistance of the longest immersed element. The longest immersed element is selected for the average product temperature if the level is above the element length + offset (item MO) + product immersion depth (item MP). Refer to figure 2.. For the description of the 4 status bytes, refer to item MQ (chapter 3.2). Item: P ecimal separator Entry format: one ASCII character;. (point) or, (comma) efault value:. (point) With the decimal separator item, a selection can be made what character is to be used for the decimal separator in all settings and measured data for level, temperature, density and pressure. The decimal separator can be:. point, comma When the decimal separator is changed, all items which holds the decimal separator, must be changed to the new format. ote: When the instrument is equipped with an XPU 2 board, the decimal separator is automatically changed in all related items. The floating point format will always contain a point as decimal separator. Page 2

13 Item description Item: EG Enable temperature transmission Entry format: one ASCII character; E or efault value: E This item Enables / isables the 877 FI to answer to a temperature request (C-record) from the host to the related level gauge. When enabled, the level gauge must not have installed a temperature option board. If this item is set to E the addressed instrument does not answer to a temperature request. Instead the 877 FI (with GA equals to the TA of the related level gauge) answers on a temperature request. If this item is set to the 877 FI does not answer to a temperature request on a GA address. Item: EM Error MPU request Protection: efault value: no write access 2200 (with MPU board) 2400 (with HPU board) 2600 (with OPU board) This item contains the most recent temperature error encountered by the MPU, HPU or OPU board. escription of the error code can be found in chapter 3.. Item: FH Fatal HPU / OPU errors Protection: no write access efault value: 00 This item counts the number of fatal HPU / OPU errors, detected by the XPU software. The maximum count is 99, additional errors are not registered. Item: FM Fatal MPU errors Protection: no write access efault value: 00 This item counts the number of fatal MPU errors, detected by the XPU software. The maximum count is 99, additional errors are not registered. Item: H0 Last fatal HPU / OPU error Protection: no write access efault value: 000:000 The first three bytes contains the last fatal error number which occurred just before the HPU / OPU board became unaccessible for the XPU. The last three bytes contains the number of 862 MIR resets as a result of lost communication or bad records. Item: M0 Last fatal MPU error Protection: no write access efault value: 000:000 The first three bytes contains the last fatal error number which occurred just before the MPU board became unaccessible for the XPU. The last three bytes contains the number of 862 MIR resets as a result of lost communication or bad records. Instruction manual 862 MIR Page 3

14 Item description Item: MG Gas immersion depth imension: determined by item L efault value: (m) for 877 FI (m) for 854 level gauges and 873 SmartRadar istance MG is introduced to reduce the heat-transfer (via thermo-well) on the spot just above the product interface. Refer to figure 2.. Item: MI Switch hysteresis imension: determined by item L efault value: (m) To prevent erratic readings by the on/off switching of temperature elements due to small level variations, a switch hysteresis is incorporated in selecting the elements. Refer to figure 2.. Item: M umber of elements Entry format: two ASCII digits efault value: 6 Item M specifies the number of elements connected to the 862 MIR (inclusive the spot element). The maximum number of elements which can be connected is 3 (i.e. 3 elements from an MRT without spot element, or 2 elements from an MRT element with spot element). When an MRT is connected with a separate gas spot, then the maximum number of elements which can be connected is (i.e. elements from an MRT without product spot element, or 0 elements from an MRT element with product spot element). A special case is when a dual spot element is connected (one product spot element and one spot element in the gas phase). Then item M becomes 0 with item MT set to xx, where xx is one of the following: PL, PS, I, CB, C or CS. Item: MO Temperature element level offset imension: determined by item L efault value: (m) istance MO defines the position of the lower end of the MRT with respect to the zero-level of the tank. For innage measurement, the switching level = actual level - MO; for ullage measurements, the switching level = MO - actual level (this is exclusive the distances MP and MI). Refer to figure 2.. Item: MP Product immersion depth imension: determined by item L efault value: (m) istance MP is introduced to reduce the heat-transfer (via thermo-well) on the spot just below the product interface. Refer to figure 2. and the description of item AP. Page 4

15 Item description Item: MQ Temperature status request Protection: efault value: no write access This item contains 4 bytes with temperature status information. For description of the status, refer to chapter 3.2. Item: MR Reference resistor imension: ohm Entry format: standard floating point format efault value: E+00 (ohm) This item contains the value of the reference resistor used in he 862 MIR. This value is: E+03 (277.5 ohm). Item: MT Temperature element type Entry format: three ASCII characters efault value: TPL Item MT specifies the type of element connected to the 862 MIR. The length of this item is 3 bytes: C3 C2 C, which have the following meaning: C3: R refers to an MRT without spot element Q refers to an MRT with spot element refers to an MRT with spot element and separate gas spot element E refers to an MRT without spot element and separate gas spot element C2 C: SA Sangamo MRT; R th = (T x ) ) SS Sangamo spot; R th = (T x ) ) BE Beacon MRT; R th = (T x ) ) BS Beacon spot; R th = (T x ) ) PL Pt00 large range ( C) PS Pt00 small range ( C) I i9 ( C) CB Cu90 Beacon MRT; R th = (T x ) ) C Cu90 ulectron MRT; R th = (T x ) ) CS Cu90 spot; R th = (T x ) ) ) T is temperature in degrees Celsius The temperature range for all copper elements is: C. ote: The dual spot configuration (C3 = or E) is not supported by MPU A0.7 and A0.8 software version. Selecting this type, will result in an MPU start-up error (EP: 027). Item: MU Test resistance Protection: no write access imension: ohm efault value: This item contains the measured test resistance used in the 862 MIR. The value of this test resistor should be: 370 ohms ±0.03% (displayed as: E+03; standard floating point format). Instruction manual 862 MIR Page 5

16 Item description Item: OB Optional board Entry format: three ASCII characters efault value: TPU This item informs the XPU board of the 877 FI about the presence of an optional board. The following selections can be made: Item: ST Store MPU MPU board installed HPU HPU or OPU board installed no option board installed Protection: C not protected The store command copies all measured level and temperature data to the related stored items. Up on reception of the store command, the temperature data is stored as follows: Average product temperature (item AP) becomes: stored average product temperature (item YP) Item: T Temperature dimension Entry format: one ASCII character; C or F efault value: C The temperature dimension can be set to: C : temperature in degrees Celsius F : temperature in degrees Fahrenheit Both dimensions have the same format: sign X X X sep X X, where sign : + or - X : digit sep : decimal separator (. or, ) Item: TF Temperature source selection Entry format: one ASCII character; I or E efault value: I For the 877 FI only. This item selects whether the temperature measurement is inside the indicator (by MPU, HPU or OPU option board) or outside (copied from the Enraf field bus). The settings are: I : internal by the MPU, HPU or OPU board E : external from the related level gauge Page 6

17 Item description Item: TU Temperature status conversion Entry format: one ASCII character efault value: T The character T (default setting) in this item is used in the temperature status byte in the field communication to indicate a reduced or not guaranteed temperature accuracy. Other characters can be used, if the host systems accepts them. The status byte is set if: out of specified temperature range last valid level used manual level used level below lowest element alternative element selected Item: U0.. UC Calculated positions of spot elements Protection: imension: efault value: no write access determined by item L IF@@<level> These 3 items contains the calculated elements lengths from the 863 MRT with respect to the lower end of the MRT. The distances of items MO, MI, MG and MP are not yet taken into account in items U0.. UC. For details on the status bytes, refer to chapter 3.2. The table below gives the element lengths for MRT with spot element (MT=QXX) and MRT without spot element (MT=RXX). Element MT = QXX MT = RXX Element MT = QXX MT = RXX U (m) 0.65 (m) U (m) 9.25 (m) U 0.65 (m).25 (m) U (m).65 (m) U2.25 (m).95 (m) U9.65 (m) 4.65 (m) U3.95 (m) 2.85 (m) UA 4.65 (m) 8.45 (m) U (m) 4.5 (m) UB 8.45 (m) (m) U5 4.5 (m) 5.65 (m) UC (m) (m) U (m) 7.37 (m) ote: For MPU software version A0.8 and lower, these element lengths are for the spot 0.3 m and for the other elements 0.35 m higher. Example: MO = 0.3 m, MP=0.5 m, MI=0. m. Element U4 (for an MRT with spot element) switches on at the level of: = 3.65 m. Item: V0.. VC Element temperatures Protection: imension: efault value: no write access determined by item T IF@@ These 3 items contains the temperature values of the individual elements. For details on the status bytes, refer to chapter 3.2. Instruction manual 862 MIR Page 7

18 Item description Item: VP Value pointer Protection: not protected Entry format: two ASCII digits, point or comma, two ASCII digits efault value: The VP item consists of 4 positions, separated in the middle: v w, x y (or v w. x y). This item, together with item VV, makes it possible to request several important calculation results. By means of the value pointer, a vector can be loaded to the MPU, HPU or OPU board. Then, with item VV the selected value is returned. For the temperature part of the MPU, HPU and OPU board, the following pointer values can be requested: v w, x y Selected value imension 0 0, 0 2 Element resistance R R3 ohm 0, 0 0 f_ Rref Hz 0, 0 f_offset_ Rref Hz 0, 0 2 R_ cable ohm 0, 0 3 Element being measured Example: VP=00,03 (Value pointer for requesting the third element resistance) VV (Item VV holds the requested third element resistance) Item: VV Pointer value Protection: no write access imension: determined by item VP efault value: Item VV holds the measured value, selected by the value pointer item VP. For the contents of this item, refer to description of item VP. Item: YP Stored average product temperature Protection: imension: efault value: no write access determined by item T IF@A This item contains the stored average product temperature value from item AP, at the time an ST command was issued. Page 8

19 Appendix Appendix A Related documents Installation guide 862 Temperature Selector Installation guide 863 MRT Multiple Resistance Thermometer Installation guide 854 Advanced Technology Gauge Instruction manual series 854 ATG level gauge Installation guide 854 XTG Servo Gauge Instruction manual series 854 XTG level gauge Installation guide 873 SmartRadar Control Unit Instruction manual 873 SmartRadar Installation guide 877 FI Field isplay & Interface Instruction manual 877 FI Field isplay & Interface Instruction manual 862 MIR Page 9

20 Appendix Appendix B ASCII table Page 20