Edwards nEXT nEXT85 - The Pump Is very Noisy or There Is Excessive Vibration or both; No Serial Comms; Fail Signal or Standby Signal Not Working

Remedy
• Remove the pump from the system and test the ulmate pressure of the pump
only.
• Check the pump for contaminaon.
Do the leak test of the pump. If the leak rate more than
1x10
-7
mbar l s
-1
(1x10
-5
Pa l s
-1
), contact us or the supplier.
Fault The pump is very noisy or there is excessive vibraon or both
Cause The rotaonal speed of the pump is same as the resonant frequency of the aached
system.
Remedy Change the natural frequency of the system or isolate the pump using exible bellows.
Cause The vibraon is transming from the rotary backing pump.
Remedy Install a exible bellows or a vibraon isolator in the backing line.
Cause The noise is irregular and increasing.
Remedy A defecve bearing. Contact us or the supplier.
Cause The pump makes a constant high pitched noise.
Remedy The rotor is out of balance. Contact us or the supplier.
Fault
No serial comms
Cause No electrical supply, loss of serial link.
Remedy Check that:
• the electrical supply is on.
• the serial link is connected.
• the serial enable line is acve.
Cause Slide switch is not in the correct posion for RS232 or RS485.
Remedy Check that:
• the electrical supply is on.
• the serial link is connected.
• the serial enable line is acve.
•
Le for RS485, right for RS232.
•
Right for parallel control and monitoring.
Cause Incorrect baud rate and node address.
Remedy Check baud rate and, if operang in mul-drop mode, the node address matches those
of the pump.
Cause Check that the red light is not on or ashing.
Remedy If LED is on, check the red alarm LED symptoms.
Fault
Fail signal or standby signal not working
Cause The serial enable line is not
acve.
Remedy Must be disconnected or driven high for use of standby and fail lines.
Cause Slide switch is not in the correct
posion for RS232 or RS485.
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B8G000880_D - Fault nding