8. Fault finding
A list of fault conditions and their possible causes is provided to assist in basic
troubleshooting. If you are not able to rectify a fault, call your supplier or your nearest
Edwards Service Centre for advice.
Fault
The pump has failed to start or has stopped
Cause
The electrical supply fuse has blown.
Remedy
Make sure that the external electrical supply is switched on and that the power
indicator LED (
Figure: Interface control panel
on page 9, (14)) is illuminated.
If the LED does not illuminate, contact us.
Cause
The motor controller has not reset after an over temperature event.
Remedy
Disconnect the main power supply and wait for at least one minute and attempt to
restart the pump. If the pump still does not start, contact us.
If the alarm indicator LED (
Figure: Interface control panel
on page 9, (5)) flashes, it
indicates that the pump has high current load from possibly a high inlet pressure/flow.
Adjust the inlet pressure/flow until the pump performance recovers.
Fault
The pump has failed to achieve the required performance
Cause
The pressure measurement technique or gauge head is not suitable or gives an
incorrect indication of pressure.
Remedy
Make sure that the vacuum measurement equipment is calibrated and is updated. The
correct gauge range must be selected for the application. Contact us for further
assistance on gauge selection, if required.
Cause
The vacuum fittings are dirty or damaged.
Remedy
Make sure that the vacuum fittings are clean and scratch free.
Cause
There is a blockage or high pressure in the exhaust line.
Remedy
Make sure that the exhaust valves fitted are not closed when the pump is in operation.
Cause
The motor controller is current limiting the supply.
Remedy
If the alarm indicator LED (
Figure: Interface control panel
on page 9, (5)) flashes, it
indicates that the pump has high current load from possibly a high inlet pressure/flow.
Adjust the inlet pressure/flow until the pump performance recovers.
Cause
The pump performance is different at the working application load.
Remedy
The pump does not have a flat performance curve, peak pumping speed can vary with
inlet pressure and gas load. Check the actual performance against the performance
curve shown in
on page 12.
Fault
The pump is noisy
Cause
The pump is contaminated with solid particles.
Page 34
A90301880_B - Fault finding
