Fox Thermal FT3 - Troubleshooting; Meter keeps power cycling

Problem Possible Cause(s) Action(s)
Meter keeps
power cycling
1. Power supply
2. Malfunction in ow
meter
3. Electromagnetic
Interference (EMI)
1. Measure power supply voltage to verify it is
stable and within operating range (refer to
power supply specs on p. 124).
2. Check meter power cycles.
3. Press and release F1 and F2 at the same time;
the display will enter Engineering screens.
4. Press F1 to get to screen #23; record power
cycle value.
5. Press F4 to return to normal operation; monitor
meter until problem returns.
6. Return to screen #23 to see if power cycles
have increased; microprocessor is resetting due
to EMI electrical noise entering the meter.
7. Check Power input and output cables
grounding and routing.
8. Return ow meter to Fox Thermal for repair
(refer to p. 136 for shipping instructions).
Flow measurement
is erratic or
uctuating
1. Very turbulent ow
2. Sensor dirty
3. Sensor broken
4. Probe not mounted
securely
5. Malfunction in ow
meter
6. Meter installed
incorrectly
1. Increase dampening (see lter settings in "Flow
Parameters" on p. 67)
2. Clean sensor (Refer to Maintenance section, p.
112)
3. Return ow meter to Fox Thermal for repair
(Refer to p. 136 for shipping instructions)
4. Remount probe (see Installation section, p.
21); must be mounted securely without
vibration. If vibration persists, choose a new
mounting location without vibration.
5. Return ow meter to Fox Thermal for repair
(Refer to p. 136 for shipping instructions)
6. Re-install meter according to instructions (Refer
to installation section, p. 21)
Troubleshooting
CAUTION! The electronics and sensor supplied by Fox Thermal are calibrated as a single
precision mass ow meter. Interchanging sensors will decrease the accuracy of the ow
meter. If you experience any problem with your model FT3 ow meter, call Fox Thermal
Customer Service Department, Technical Assistance at (831) 384-4300.
Troubleshooting | 116
Model FT3
Troubleshooting