Edwards E1M40, Instruction Manual

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© Edwards Limited 2007. All rights reserved. Page 21
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Operation
A344-02-880 Issue J
4 Operation
4.1 Gas-ballast control
Use the gas-ballast control ( Figure 1 , item 11) to change the amount of air (or inert gas) introduced into the
low-vacuum stage of the pump. Use of the gas-ballast will prevent the condensation of vapours in the pump. The
condensed vapours would contaminate the oil.
Turn the gas-ballast control fully clockwise:
z
to achieve ultimate vacuum
z
to pump dry gases.
Turn the gas-ballast control anti-clockwise to open. Use the gas-ballast control fully open:
z
to pump high concentrations of condensable vapour
z
to decontaminate the oil.
When you operate the pump with the gas-ballast control open, there is an increased rate of oil loss from the pump.
4.2 Start-up procedure
If the oil is contaminated, or if the pump temperature is below 13°C, or if the supply voltage is more than 10% below
the lowest voltage specified for the motor, the pump may operate at reduced speed for a few minutes.
1. Switch on the electrical supply to the pump.
2. Check that the oil-level in the sight-glass drops slightly (3 to 5 mm) after start-up. This shows that the pump has
primed with oil.
3. If the pump fails to prime, operate the pump with the inlet open to atmosphere for approximately 30 seconds.
Then isolate the inlet and check that the oil-level drops 3-5 mm.
4. If you want to achieve ultimate vacuum, to pump condensable vapours or to decontaminate the pump oil, refer
to the procedures in Sections 4.3 , 4.4 and 4.5 respectively. Otherwise, open the vacuum system isolation-valve.
WARNING
We do not recommend that you use the E1M40, E2M40, E1M80 and E2M80 pumps to pump
hazardous substances.
WARNING
Do not block the pump outlet or allow the outlet pressure to rise above 1.5 bar absolute. If you do,
the oil box may fracture: this may cause injury to people.