Edwards xds35i, Инструкция по эксплуатации, Страница: 21 / 40

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A730-01-880 Issue E
4 Operation
4.1 Use of gas ballast control
You can use the gas ballast control to optimise the performance of the scroll pump for your application. The
performance characteristics of the pump with the different ballast settings are shown in
Section 2.2.2 . You can
change the position of the gas ballast control when the pump is off or when the pump is operating.
4.1.1 Gas ballast control
Use the gas ballast control to change the amount of air introduced into the final stage of the pump. Use of gas ballast
will reduce the condensation of vapours in the pump; the condensates would contaminate the pump. You can turn
the gas ballast control to select one of the three positions, as follows:
To select no gas ballast, turn the control position to '0'. Use this setting:
z
to achieve ultimate vacuum
z
to pump dry gases.
To select low flow gas ballast, turn the control to position 'I'. Use this setting:
z
to pump low concentrations of condensable vapours
z
to decontaminate the pump.
To select high flow gas ballast, turn the control to position 'II'. Use this setting:
z
to pump high concentrations of condensable vapours
z
to clear excess vapours after processing.
4.2 Start up procedure
CAUTION
A fine dust may be emitted from the exhaust of the scroll pump during start up, particularly when the pump is
new or if new tip seals are fitted. Refer to
Section 5.6 for further information when fitting new tip seals.
Use the procedure below to start up the pump:
1. Ensure that any vacuum system isolation valve is closed (if fitted).
2. Connect a suitable lead from the power supply to the electrical socket at the side of the pump.
3. Switch on the electrical supply to the pump, using the on / off switch on the motor.
4. Always use the on / off switch to start / stop the pump.
5. Open the vacuum system isolation valve (if fitted).
WARNING
Ensure that your system design does not allow the exhaust pipeline to become blocked.