Edwards 30B5M, Инструкция по эксплуатации

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B064-04-880 Issue F
Page 26 © Edwards Limited 2008. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Operation
1. Close the vacuum system isolation valve (3), close the roughing valve (5) and open the backing valve (7) and the
holding valve (12, if fitted).
2. Open the vacuum system air-admittance valve (4).
4.8 Re-evacuation of your vacuum system
1. Close the vacuum system air-admittance valve (4) and any other openings to atmospheric pressure.
2. Close the backing valve (7) and open the roughing valve (5) and holding valve (12, if fitted).
3. When a system pressure of less than 2 mbar (2 x 10
2
Pa) is reached, close the roughing valve (5) and the holding
valve (12, if fitted) and open the backing valve (7).
4. Open the vacuum system isolation valve (3).
4.9 Pump shut-down
As described in Section 1.8 , when the pump is switched off, the heaters in the pump will absorb moisture: this will
cause a decrease in the insulation resistance of the heaters. To avoid the absorption of moisture when the pump is
in an environment of high ambient humidity, we recommend that you maintain the pump boiler temperature at a
temperature between 20 and 30 ºC above ambient temperature. Ensure that the boiler does not get too hot; if it
does, the pump fluid may vaporise and contaminate the vacuum system.
The following method of shut-down ensures that the 30B5M pump is left evacuated and prevents absorption of air by
the pump fluid.
When you subsequently start-up, evacuate the system to a pressure of about 10 mbar (1 x 10
3
Pa) through the backing
valve before you switch on the 30B5M heaters.
1. Refer to Figure 7 . Close the vacuum system isolation valve (3).
2. On an unconfigured pump, switch off the electrical supply to the pump. On a control configured pump, move the
Heater Power switch ( Figure 2 , item 3) to the off position.
3. Leave the pump to cool down for at least four hours; the backing pump must be left switched on throughout this
time.
4. After the cool-down period, close the backing valve (7).
5. Open the backing pump air-admittance valve and switch off the backing pump (8). If you do not admit air to the
backing pump, backing pump oil may be drawn into the backing pipeline.
6. Turn off the cooling-water supply when the boiler temperature falls to 100 ºC.
7. If required, open the vacuum system air-admittance valve (4) to admit air into the system.