Alternative Valve Connected To The Vacuum System; Operation With Parallel Control And Monitoring; Start The Pump With Parallel Control - Edwards nEXT730D Instruction Manual

If the nEXT pump is being controlled with an Edwards TIC Turbo and Instrument
Controller or TIC Turbo Controller, the TAV solenoid valve can be driven from the TIC.
Refer to the TIC Instruction Manuals for more information.

7.2.4 Alternative valve connected to the vacuum system

When using another vent valve, ensure that a suitable vent restrictor is fitted to the
vacuum system to limit the rate of pressure rise.
Refer to Table: Vent restrictor orifice diameter if venting the vacuum system chamber
information about vent restrictor sizes. If a suitable vent restrictor is not fitted, open the
vent valve only after the speed of the pump has fallen to 50% of full rotational speed.
Vacuum system volume (litres)

7.3 Operation with parallel control and monitoring

7.3.1 Start the pump with parallel control

CAUTION:
Do not operate the pump with its rotor exposed. Before operating the pump it must
first be connected to the vacuum system. If the pump is operated with its rotor
exposed, the pump rotor can cause injury as it rotates at very high speeds and the
rotating blades might not be visible.
WARNING:
Do not move the pump whilst it is running. The gyroscopic forces generated by this
movement can cause excessive use of the back-up bearing and may result in
catastrophic failure of the pump.
CAUTION:
When power is restored following a power cut, the pump will restart automatically.
The pump must remain connected to the vacuum system to prevent risk of injury.
In parallel control the pump will accelerate to full operating speed when started.
Start the nEXT pump by linking the start/stop control input to the 0 V control reference
on the logic interface connector.
The green indicator on the motor controller will illuminate when the pump reaches
normal speed. This is 80% of full rotational speed by default but a different value may
have been selected to suit the application.
B8J200880_D
300812671_002_C3
B8J200880_D - Operation
< 20
< 10
< 5
< 2
Page 79
Orifice diameter (mm)
< 1.0
< 0.7
< 0.5
< 0.35
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