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1. Troubleshooting
Symptom
Causes
Check point & countermeasure
Pump does not start
Defective electrical
wiring line
Confirm wiring between FDC-1 and solenoid valve for pump.
Confirm wiring between FDC-1 and proximity switch.
NO and NC proximity sensor of pump supply are being input to FDC-1
as right and left reversed.
Defective pump proximity sensor.
After power on to FDC-1, confirm output voltage of proximity sensor
without supplying air to pump.
FF pump: voltage between white and black is approx. 24V.
FH, FA pump: voltage between black and blue is approx. 24V.
FS pump: voltage between white and black is approx. 24V.
FW pump: voltage between white and black is approx. 24V.
If the above voltages close to 0V, it seems defective.
Electrode (leak sensor) is conducted.
The sequence is arranged to let inter-lock work among pump, FDC-1
and equipment when pump starts.
Defective air piping
line
Air supply is not provided correctly to the preliminary (IN) side of
Electro-pneumatic regulator EV2000.
Defective solenoid valve.
Minimum air pressure for drive becomes higher due to solenoid valve
run down.
Exhaust outlet of solenoid valve or QEV is covered or closed.
Wrong IN and OUT connection of Electro-pneumatic regulator
EV2500.
Wrong IN and OUT connection of QEV.
Air piping for pilot is not arranged in spite of using solenoid valve for
external pilot way.
Defective liquid
piping line
Liquid valve installed at both sides of pump inlet and outlet are closed.
The sequence is arranged for not to open liquid valve when pump starts
Sufficient filtration size is not secured and it becomes high load due to
entangled filter by air.
Pump stops soon
after it starts.
Time up alarm
outputs.
Improper setting
Too little flow rates.
Resettle value of setting screen No.4.
When the pump discharge side pressure gets lower, the flow control
function of FDC-1 lowers the supply air pressure. When the air
pressure gets lowered, it may happen the pump stops because enough air
pressure to drive the pump can not be kept. If this happens, change the
value on Setting screen No. 6 on page 20 to the value at which the pump
can not stop.
Confirm wiring between FDC-1 and Electro-pneumatic regulator
EV2500.
