4.7.3 Check the direction of rotation
CAUTION:
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
. 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
phase electrical connections: 200–230 V
and
Figure: Three-phase electrical
▪
Refit the cover to the terminal-box.
4.8 Inlet and outlet connections
WARNING:
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
(item 4)).
Take note of the following information when connecting the pump to the vacuum
system. Refer to
on page 50 for 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.
We recommend using manufacturers 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.
In any of the following circumstances, fitting an oil mist filter to the pump outlet is
recommended:
03/2021 - ©Edwards Limited
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A65201880_AA
A65201880_AA - Installation