BOC E2M28, Instruction Manual

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E2M28 and E2M30 Rotary Vacuum Pumps
IN
STALLATION
PAGE
20
Issue K 20 Jul 05
3.7.2 Check the direction of rotation
1. With the pump inlet still unconnected, watch the motor cooling-fan through the motor fan-cover,
switch-on the electrical supply to the motor for a few seconds, then switch off the electrical supply
again.
2. 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 Figures 8 and 9.
• Refit the cover to the terminal-box.
3.8 Connect the pump inlet
Take note of the following information when you connect the pump to your vacuum system. Refer to
Section 7.4 for details of the accessories mentioned below.
• For optimum pumping speeds, ensure that the pipeline connected to the inlet-port is as short as
possible and has an internal diameter not less than the inlet-port diameter.
• Support the vacuum pipelines to prevent loading of the coupling-joints.
• If necessary, incorporate flexible bellows in your system pipelines to reduce the transmission of
vibration and to prevent loading of coupling-joints. If you use flexible bellows, you must ensure that
you use bellows which have a maximum pressure rating which is greater than the highest pressure
that can be generated in your system. We recommend that you use BOC Edwards flexible bellows.
• Use a suitable inlet catchpot if you pump condensable vapours or if you use the pump for very dusty
applications.
• Ensure that sealing surfaces are clean and scratch-free.
Connect your vacuum system to the inlet-port (Figure 1, item 6). To make this connection, you can:
• Connect to the NW25 flange supplied: use the NW25 centring-ring and 'O' ring supplied.
• Remove the NW25 flange and connect to the 1 inch BSP threaded hole.
• Use an NW25 to 28 mm bore tube adaptor available as an optional accessory, see Section 7.4.11.
CAUTION
Ensure that the motor rotates in the correct direction. If it does not, the pump and your vacuum
system can become pressurized when you operate the pump.