Edwards A652-07-903, Инструкция по эксплуатации

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A652–07–880 Issue C
Page 24 © Edwards Limited 2007. All rights reserved.
Edwards and the Edwards logo are trade marks of Edwards Limited.
Operation
4.3 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 ( Figure 1 , item 8). If the oil is cloudy or discoloured,
continue with the procedure at Step 2 below.
2. Close the vacuum system isolation-valve.
3. Operate the pump until the oil is clear.
4.4 Unattended operation
The E-LAB 2 is designed for unattended operation under the normal operating conditions specified in Section 2 .
However, we recommend that you check the pump at regular intervals of not more than 14 days, or more frequently
if you pump high volumes of gas or vapour.
To automatically decontaminate the pump oil, and to ensure that the correct pump operating temperature is
maintained, we recommend that you control the electrical supply to the pump and the operation of the vacuum
system isolation-valve through a time-switch: refer to
Table 4 .
The motor is protected by an overload device which isolates the E-LAB 2 from the electrical supply when critical
temperature or current levels are exceeded. The overload device resets automatically when the motor has cooled.
When you check the E-LAB 2, make sure that the pump is not going through a repetitive cycle of thermal overload
failures and automatic resets. If necessary, reduce the thermal load from the pumped gases, to prevent overheating
of the pump.
4.5 Shut-down
We recommend, as described in the procedure below, that you decontaminate the oil before you shut down the
pump; this will prevent damage to the pump by the contaminates in the oil.
1. Refer to Section 4.3 and decontaminate the oil, as required.
2. Close the vacuum system isolation-valve (if not already closed).
3. Use the on/off switch to switch off the pump.
4. Switch off the electrical supply to the pump.
Table 4 - Recommended time-switch settings
Time Pump operation Isolation-valve operation Function
At least half an hour before
the pump is required for use Switch on Closed Pump warm-up time
During operation Leave on Open or closed, as
required by pumping
system operation Maintain the operating
temperature of the pump,
decontaminate the pump oil
At least half an hour after
use Leave on Closed Decontaminate the pump oil
After the decontamination
time Switch off Closed Ready for future use