The Pump Is Very Noisy Or There Is Excessive Vibration Or Both; No Serial Comms; Fail Signal Or Standby Signal Not Working - Edwards nEXT730D Instruction Manual

Cause The inlet pressure is poor.
▪ Remove the pump from the system and test the ultimate pressure of the
Remedy
pump alone (refer to ).
▪ If inlet pressure is poor, check the pump for contamination and refer to .
▪ Leak test the pump. If the leak rate > 1x10
contact the supplier or Edwards.
Fault

The pump is very noisy or there is excessive vibration or both

Cause The pump rotational speed is the same as the resonant frequency of the attached
system.
Remedy Change the natural frequency of the system or isolate the pump using flexible
bellows.
Cause The vibration is being transmitted from the rotary backing pump.
Remedy Fit flexible bellows or a vibration isolator in the backing line.
Cause The noise is irregular and getting progressively worse.
Remedy There is a defective bearing. Contact the supplier or us.
Cause The pump is making a constant high pitched noise.
Remedy The rotor is out of balance. Contact the supplier or us.
Fault

No serial comms

Cause No electrical supply, loss of serial link.
Remedy Check that the electrical supply is on, that the serial link is connected and that the
serial enable line is active.
Cause Slide switch is not in the correct position for RS232 or RS485.
▪ Check that the electrical supply is on, that the serial link is connected and
Remedy
that the serial enable line is active.
▪ Left for RS485, right for RS232.
▪ Right for parallel control and monitoring.
Cause Incorrect baud rate and node address.
Remedy Check baud rate and, if operating in multi-drop mode, the node address matches
those of the pump.
Cause Check that the red light is not on or flashing.
Remedy If LED is on, perform the checks against the red alarm LED symptoms
Fault

Fail signal or standby signal not working

Cause The serial enable line is inactive.
Remedy Must be disconnected or driven high for use of standby and fail lines.
Cause Slide switch is not in the correct position for RS232 or RS485.
Remedy Left for RS485, right for RS232.
Right for parallel control and monitoring.
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