Operation
27
6.4
Topping up the operating fluid
If the operating fluid has reached its minimum filling level, the operating fluid must be
topped up. The fluid can be topped up during operation in the final vacuum.
Filling up the operat-
ing fluid
Unscrew operating fluid filler screw 91.
When the pump is at operation temperature, top up the operating fluid up to the "max."
marking.
Fig. 15: Filling up the operating fluid
Screw in operating fluid filler screw 91.
6.5
Switching off and venting
The pump can be switched off in any pressure range.
Turn off the vacuum pump, vent to atmospheric pressure and allow to cool.
Disconnect intake line after switching off the pump so that operating fluid does not flow
back into the vacuum line.
– An electro-pneumatic activated shut-off valve (see Accessories) can be used for
this purpose; the valve's control can be coupled with the motor voltage.
Open magnetic venting valve at measurement connection 50 and vent the pump.
– To prevent premature venting the venting valve can be coupled with the shut-off
valve's position indicator.
If the ambient temperature is less than 0 °C, the cooling water must be drained at Pos.
62 after the pump is switched off and after prolonged down time
.
91
m ax
m in.
CAUTION
Danger of backflow of operating fluid into the intake line!
Contamination of the connected vacuum system!
Because the pump has no internal safety valve, install an additional shut-off valve in
the intake line.
Shut off the intake line and vent the pump immediately after switching off the pump.
NOTICE
Damage to drive and pump because of oil stroke when switching on!
If the pump is not vented sufficiently after switching off, the rotor can rotate backwards
and suck operating fluid into the suction chamber.
Always vent the pump sufficiently to avoid rising operating fluid.
