Fluid Components International MT91 Maintenance

CHAPTER 4 - MAINTENANCE FLUID COMPONENTS INTL

4. Maintenance

The flowmeter requires very little maintenance. There are no moving parts or mechanical parts subject to wear in the
flowmeter. The sensor assembly which is exposed to the process media is all stainless steel construction with nickel
braze and is only susceptible to chemical attack based on the corrosion relationship of the RTD thermowell material
with the process media.

Maintenance

Without detailed knowledge of the environmental parameters of the application surroundings and process media, FCI
cannot make specific recommendations for periodic inspection, cleaning, or testing procedures. However, some
suggested general guidelines for maintenance steps are offered below. Use your operating experience to establish the
frequency of each type of maintenance.

Calibration

Periodically verify the calibration of the output and recalibrate if necessary. See Chapter 5. FCI recommends every
18 months at a minimum.

Warning:

Caution:

To avoid hazards to personnel, ensure that all environmental isolation seals are properly

maintained.

The flow transmitter contains electrostatic discharge (ESD) sensitive devices. Use standard ESD
precautions when handling the flow transmitter. See Chapter 2, Installation for ESD details.

Electrical Connections

Periodically inspect cable connections on terminal strips and terminal blocks. Verify that terminal connections are
tight and physically sound with no sign of corrosion.

Remote Enclosure

Verify that the moisture barriers and seals protecting the electronics in the probe assembly enclosure and the
electrical assembly enclosure are adequate and that no moisture is entering those enclosures.

Electrical Wiring

FCI recommends occasional inspection of the system’s interconnecting cable, power wiring and probe assembly
wiring on a “common sense” basis related to your application environment. Periodically the conductors should be
inspected for corrosion and the cable insulation checked for signs of deterioration.

Flow Element Connections

Verify that all seals are performing properly and that there is no leakage of the process media. Check for
deterioration of the gaskets and environmental seals used.

Flow Element Assembly

Periodically remove the flow element for inspection based on historical evidence of debris, foreign matter, or scale
build-up and appropriate plant shutdown schedules and procedures. Check for corrosion, stress cracking, and/or
build-up of oxides, salts, or foreign substances. The thermowells must be free of excessive contaminants and be
physically intact. Any debris or residue build-up could cause inaccurate switching. Clean the probe, as necessary,
with a soft brush and available solvents (compatible with Stainless Steel).

Doc. No. 003185 Rev. B 4 - 1

Model MT91 Multipoint Flowmeter

FLUID COMPONENTS INTL CHAPTER 4 - MAINTENANCE

Model MT91 Multipoint Flowmeter 4 - 2 Doc. No. 003185 Rev. B