To Pump Condensable Vapours; To Decontaminate The Oil; Unattended Operation - Edwards RV3 Instruction Manual

4.5

To pump condensable vapours

Use gas-ballast (gas-ballast control in position 'I' or 'II') when there is a high proportion of condensable vapours in
the process gases.
1. Close the vacuum system isolation-valve.
2. Turn the mode selector fully clockwise to select High Vacuum mode  or fully anticlockwise to select High

Throughput mode , as required (refer to
3. Turn the gas-ballast control to high flow (position 'II') and operate the pump for 30 minutes to warm the oil; this
will help to prevent vapour condensation in the pump.
4. Set the gas-ballast control to the position required for the application (refer to
Table 3 and Table 4).
5. Open the vacuum system isolation-valve.
After pumping condensable vapours, decontaminate the oil if necessary: use the procedure in
4.6

To decontaminate the oil

The oil in the pump should be clear; if the oil is cloudy or discoloured, it is contaminated with process vapours.
1. Look at the condition of the oil in the oil-level sight-glass
continue with the procedure at Step 2 below.
2. Close the vacuum system isolation-valve.
3. Turn the mode selector fully anticlockwise to select High Throughput mode
flow (position 'I').
4. Operate the pump until the oil is clear.
4.7

Unattended operation

The RV pump is designed for unattended operation under the normal operating conditions specified in
However, Edwards recommends checking the pump at regular intervals of not more than 14 days, or more frequently
if pumping high volumes of gas or vapour.
On single-phase pumps, the motor is protected by an overload device which isolates the pump from the electrical
supply when critical temperature or current levels are exceeded. The overload device resets automatically when the
motor has cooled. When checking the pump, make sure that the pump is not going through a repetitive cycle of
thermal overload failures and automatic resets. If necessary, change the mode selector to High Throughput mode
and reduce the thermal load from the pumped gases, to prevent overheating of the pump.
© Edwards Limited 2018. All rights reserved.
Edwards and the Edwards logo are trade marks of Edwards Limited.
Section 4.2.2).
(Figure 1, item 8). If the oil is cloudy or discoloured,
A652–01–880 Issue Y
Section 4.2.3 and the data in
Section 4.6.

. Set the gas-ballast control to low
Section 2.1.

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