Edwards nEXT400 User Manual

Use applicable vacuum tubing and connectors to connect the NW ange of the backing
port t
o the backing pump. If necessary, use exible pipe or bellows to decrease the
transmission of vibraon from the backing pump to the pump.
We recommend you to use our EM, RV or XDS Scroll backing pump. The recommended
size of backing pump is given in Table: nEXT pumps technical data. A larger or smaller
backing pump can be used, depending upon the applicaon it is intended for.
The pumps are applicable to use with diaphragm backing pumps but the eect of higher
backing pressure on the pump's performance and cooling requirements must be noted.
Refer to Table: nEXT pumps technical data and General technical data on page 18.
4.3.6 Interstage connecon (variants only)
Use applicable vacuum tube and connectors to connect the interstage port to the
vacuum system or to the outlet ange of the other turbo or compound
turbomolecular pump (if using an 'i' nEXT pump to back other pump). Keep the inlet
strainer in the interstage port only if you are sure that debris cannot enter the interstage
port.
4.4 Purge gas connecon
4.4.1 Recommended purge gas ow
The recommended purge gas ow for typical applicaons is 25 sccm (0.42 mbar l s
-1
,
42 Pa l s
-1
). The ow protects the pump when you pump the oxygen in concentraons
more than 20% by volume.
The ow rate of the purge gas must be in a range given in Purge gas specicaon on
page 28. To limit the ow rate, use a ow controller or a pressure regulator and
calibrated ow restrictor. The PRX10 purge restrictor accessory is applicable for the
purpose. Refer to Accessories on page 99.
4.4.2 Connect the purge gas
Note:
The purge gas must comply with the specicaon given in Purge gas specicaon on
page 28.
1. To supply the purge gas to the pump, remove the plug installed in the purge port.
2. To install a vent port adaptor, refer to Accessories on page 99.
3. Connect the purge gas supply to the vent port adaptor.
4.5 Electrical installaon
WARNING: ELECTRICAL INSTALLATION
Make sure that the electrical installaon of the pump is in accordance with the
regional and local codes and conforms to local and naonal safety requirements. The
pump must be connected to an applicable power supply unit with an applicable earth
(ground) point.
04/2022 - ©Edwards Limited
Page 43B80000880_G
B80000880_G - Inst
allaon

Edwards nEXT400 Specifications

General

Brand	Edwards
Model	nEXT400
Category	Water Pump
Language	English