FCI ST100 series Installation, Operation & Maintanance Manual

Also see for ST100 series: Configuration software manual Configuration software manual Manual Operation manual

Contents

FCI ST100 series Installation, Operation & Maintanance Manual Manual pdf 48 page image

TROUBLESHOOTING ST100 Series Flow Meter42 Fluid Components International LLCVerification of the ElectronicsCheck the Flow Transmitter Power Supply VoltagesCheck the voltages shown in the table below with a DMM set to voltage. The readings are taken on the power supply board at connector P2.Pin Number Expected Power Supply VoltageDigital 5 VDC: P1 to P2 4.975 to 5.025Analog 24 VDC: P3 to P4 23.975 to 24.025Instrument Power Supply VoltagesIf the voltage checks correspond to the levels shown in the table, the power supply is functioning properly.Transmitter Circuit Calibration Check (Delta R Verification)Equipment Needed• FES-200 Flow Element Simulator with proper cable for FCI transmitter model• Digital Multimeter• Delta R Calibration Data Sheet (serial number specific by instrument and group)• Precision 250 ohm resistor (recommended)Alternate Tool for FES-200• 2 - Precision Decade Resistance Box, 0.1% (1 kΩ large step, 0.01 Ω small step)Note: If the flow meter’s parameters have been changed, calibrations may be inaccurate or factory authorized changes have beenmade. Consult a factory service representative.Each flow meter is provided with a Delta R data sheet which is a table listing the differential resistance values that correlate to the flow meter’scalibration. Resistance substitution instruments like the FES-200 can be used to check instrument calibration and verify correct operation of the flowtransmitter using the Delta R data sheet.To verify the transmitter is working properly, the sensor head must be disconnected and precision resistance (Delta R) values from the FES-200 aresubstituted. Then by measuring the transmitter output and display it can be determined whether the transmitter is still within factory specification.Delta R Check1. Verify the Delta R data sheet has the same serial number and group number as the flow meter calibration that is being verified.2. Power off the transmitter.3. Disconnect the instrument’s sensor and connect the FES-200 input connector into the transmitter. See Figures 22 – 24 for integral orremote configuration diagrams. Precision decade boxes can be used in place of the FES-200. See Figure 25 for decade box wiring.4. Connect a DMM to the transmitter 4 – 20 mA output by either method A or B:A. To read 1 to 5 volts, disconnect both output loop wires and connect a precision 250 Ω resistor across the output terminal(Figure 20). Then connect the DMM, set to DC volts (V), across the resistor to read the voltage drop.B. To read 4 to 20 mA current, disconnect the output loop and connect the DMM, set to milliamps (mA), in series with the outputcircuit (Figure 21) to read the current flow.Warning: Explosion Hazard. Do not disconnect equipment when flammable or combustible atmosphere is present. Operator assumesresponsibility for all safety concerns relating to interrupting and reapplying power to their instrumentation.Safety Instructions