Check The Direction Of Rotation; Inlet And Outlet Connections - Edwards RV3 Instruction Manual

3.7.3

Check the direction of rotation

Ensure that the pump-motor rotates in the correct direction. If it does not, the pump and vacuum system can
become pressurised.
1. Refer to Figure 1. Watch the motor cooling-fan through the motor fan-cover (13).
2. Switch-on the electrical supply to the motor for a few seconds.
3. Check that the motor cooling-fan rotates in the correct direction shown by the arrow on the motor mounting
plate. If the direction of rotation is incorrect:
Switch off the electrical supply immediately.

Isolate the pump from the electrical supply.

Remove the terminal-box cover and swap wires L1 and L3: see

Refit the cover to the terminal-box.

3.8

Inlet and outlet connections

Connect the exhaust to a suitable treatment plant to prevent the discharge of dangerous gases and
vapours to the surrounding atmosphere. Use a catchpot to prevent the drainage of contaminated
condensate back into the pump.
Before connecting the pump to the vacuum system, fit the centring-ring and inlet-filter (supplied with the pump) to
the pump inlet-port (see Figure 3
Take note of the following information when connecting the pump to the vacuum system. Refer to
details of the accessories mentioned below. Use standard NW25 fittings (not supplied) when connecting the pump.
For optimum pumping speeds, ensure that the pipeline connected to the pump-inlet is as short as possible

and has an internal diameter of 25 mm or larger.
Support the vacuum pipelines to prevent loading of the coupling-joints.

If necessary, incorporate flexible bellows in the system pipelines to reduce the transmission of vibration and

to prevent loading of coupling-joints. If using flexible bellows, ensure that bellows which have a maximum
pressure rating which is greater than the highest pressure that can be generated in the system are used.
Edwards recommends using Edwards flexible bellows.
Use a suitable inlet trap if pumping condensable vapours or if the pump is to be used for very dusty

applications.
Use a suitable valve to isolate the pump from the vacuum system if pumping condensable vapours or to

maintain vacuum when the pump is switched off.
Ensure that sealing surfaces are clean and scratch-free.

© Edwards Limited 2018. All rights reserved.
Edwards and the Edwards logo are trade marks of Edwards Limited.
CAUTION
WARNING
(item 4)).
A652–01–880 Issue Y
Figure 5 and Figure 6.
Section 7 for
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