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15.11 SAMPLE PUMP PROBLEMS
15.11.1 Electrical problems
15.11.1.1 Pump runs but the green indicator on the starter box is off
Probable causes Action
1
Indicator failure.
Check power supply to indicator lamp.
Check indicator lamp.
15.11.1.2 Pump should be running but is off
Probable causes Action
1
3-phase power supply failure.
Check if the 3-phase power supply is switched on.
Check the fuses of the 3-phase power supply. the
water supply to the pump.
2
Thermal trip of the pump.
Check the power on the contactor terminals (1,2), these
should be 24 VDC.
Also check also for correct polarity.
Check the 24 VDC power supply in the EPU.
Check the connections between the starter box and the
EPU.
NOTE:
If the motor repeatedly trips out on thermal trip, check the motor and pump for binding
or blockages etc. do not force the motor to run.
15.11.2 Pump related problems
NOTE:
During forward flush and in sample mode, normal operating conditions are:
Pump discharge pressure 5 to 8 bar. (0.5 to 0.8 MPa).
Pump suction pressure 0 to 1 bar. (0 to 0.1 MPa).
(Pressures may vary from one installation to another)