FCI ST100A Series, Installation, Operation And Maintenance Manual

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ST100A Series Flow Meter TROUBLESHOOTING
Fluid Components International LLC 93
5 TROUBLESHOOTING
Warning: Instrument testing/troubleshooting limited to qualified personnel only. The operator assumes all responsibilities for
safe practices while troubleshooting.
Caution: The flow transmitter contains electrostatic discharge (ESD) sensitive devices. Use standard ESD precautions when
handling the flow transmitter. See ESD Precautions , page 16 for details.
Non-Maintenance Observations
At this point, observe the system setup to verify operation. No disassembly or testing is required at this time.
Check Serial Numbers
Verify that the serial number of the flow element(s) and the flow transmitter are the same. The flow element(s) and the flow transmitter are
a matched set. Neither can work independently of the other nor can they be swapped with similar units from another system.
Check Input Power
Check for intact fuses. Verify that the AC power source is connected and turned on.
Check Instrument Installation
Review the instrument installation information given in the Installation section to verify correct mechanical and electrical installation. Be sure the
connectors are firmly mated, and the wires are firmly attached to the connector. (Be sure the wires are inserted between the metal clamps and not
between the clamp and plastic connector enclosure.) Verify correct wiring per wiring diagram in APPENDIX A , page 105 .
Check for Moisture
Check for moisture in the enclosures. Moisture on the electronics can cause faulty operation.
If a component of the process media is near its saturation temperature, then the component may condense on the sensing points. Liquid
on the sensing points can cause measurement errors.
Check Application Design Requirements
Application design problems usually occur with first time application instruments, although the design should also be checked on
instruments that have been in operation for some time. If the application design does not match field conditions, errors occur.
1. Review the application design with plant operation personnel and plant engineers.
2. Ensure that plant equipment such as pressure and temperature instruments conform to the actual conditions.
3. Verify operating temperature, operating pressure, line size, and gas medium.
Check the General Process
Check all inputs and outputs to the system. Verify pump ratings and check damper or valves that might be open or closed causing the flow
to be different from that which would be expected.