118_4416655_Rev06

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Average temperature measurement with VITO temperature probes ___________________________________________________________________________ 2.3 Operation 2.3.1 Display For operation of the display and the information on it (if applicable), refer tot the instruction manual of the related level gauge or indicator. Below, only an overview is given which display formats gives information about the average temperature measurement. Display format A C D Displayed information Product level and average product temperature Average gas temperature and status Average product temperature and status 2.3.2 Data items Table 2 – 3 lists a number of data items. They contain measured data, verification data and error data. The verification data can be used to check the results of certain steps in the measuring sequence. The temperature status indicates the validity of the measured data. The error data provides low level error information about the temperature measurement (refer to section 2.4). Item AG AP MQ MU U0 - UF V0 - VF VV RW EM FH F0 Table 2 – 3 Description Measured/ Calculated data Average gas temperature Average product temperature Temperature status request (refer to section 2.4.2) Measured test resistance (floating point format); Must be: 166.5 Ω ± 0.03% Calculated spot positions (see below) Spot temperatures (see below) Verification data Refer to description at section 2.4.3 Thermocouple wiring connection sequence Diagnostic data Error request (refer to section 2.4.1). Fatal errors Last fatal error Item V0 is the temperature of the lowest spot element. The calculated spot position item U0 corresponds with item V0. Refer to figures 2.1 and 2.2 to locate the lowest spot (L) with each particular temperature probe model. Instruction manual VITO Page 16
Average temperature measurement with VITO temperature probes ___________________________________________________________________________ 2.4 Troubleshooting 2.4.1 Temperature error request (item EM) This item helps you configuring correctly by the most recent temperature error encountered by the option board. xx00 No error, value at initialisation xx11 No reply on initial HART commands Communication error. Check connection level gauge – 762 VITO interface, or change 762 VITO interface or option board. xx50 Pt100 (or spot 0) error Brown wire connected to CN1 A-1 (or orange wire connected to CN2B-1) not connected . xx51 Spot 1 (or Pt100) error Blue wire to CN2B-1 (or brown wire to CN1A-1) not connected xx52 Spot 2 error Blue wire to CN2A-2 not connected xx64 Spot 14 error Blue wire to CN5A-2 not connected xx65 Spot 15 error Yellow wire to CN5A-1 not connected xx70 Sub-system error Data from 762 VITO not valid. Reset instrument; if error persist, replace 762 VITO interface or, open Pt100 wiring (red – brown wires) xx71 Wrong probe connection Thermocouple wires of VITO sensor connected wrongly (blue and yellow wires) or, isolation resistance VITO sensor too low (replace VITO probe) xx77 Wrong Pt100 connection Brown and red wires of VITO sensor connected wrongly xx80 R test error Measurement on test resistor failed. Reset instrument; if error persist replace 762 VITO interface or VITO probe xx84 Standard deviation too large EMC influence (check cable shields) or defective 762 VITO interface xx92 No data available Communication error between 762 VITO interface and level gauge. Check wiring; replace 762 VITO interface or option board. xx98 No temperature sources found No VITO temperature probe (and no RTD) connected xx: 22 for MPU emulation With error codes xx50 to xx65, connector numbers are mentioned 24 for HPU emulation Refer to Installation guide 762 VITO Interfaces & VITO, MTT, LT and MRT probes 30 for HCU emulation for the location of these connectors. 2.4.2 Temperature status request (item MQ) Temperature status request item contains four status bytes (Byte 0, Byte 1, Byte 2, Byte 3) of the option board. For decoding, refer to the ASCII table in appendix A. Status byte 0: Contains the characters ‘0’ ÷ ‘F’, indicating the highest submersed spot element of the temperature probe. At start up: ‘I’. Status byte 1: Status byte 2: Bit 0: General temperature fail Bit 0: Last valid level used 1: Fail in average product temperature 1: Manual level used 2: Fail in average gas temperature 2: Level time out 3: Level exceeds lowest spot element 3: Device not calibrated 4: Level exceeds highest spot element 4: Exceeding differential temp, range 5: Spot element fail (one or more spots defect) 5: Out of specified temperature range 6: 1 6: 1 7: 0 7: 0 Status byte 3: Bit 0: No previous store command 1-5: 0 6: 1 7: 0 Note: Only the bits which are set to ‘1’ have an active status. Instruction manual VITO Page 17
Page 1: Instruction manual VITO interface a
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Page 8 and 9: Introduction VITO Interface and ave
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Page 38 and 39: Water bottom measurement __________
Page 46 and 47: Appendix __________________________
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Page 50 and 51: Notes _____________________________
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