Oerlikon Leybold Vacuum 960 862, Operating Instructions Manual

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30 GA02319_002_03 - 07/2007 - © Oerlikon Leybold Vacuum
Operation
4.2 Switching off / Shutdown
The intake port of the SOGEVAC
®
SV630 B contains an anti-suckback valve
which closes the intake port when the pump is switched off, thus maintaining
the vaccum in the connected apparatus and preventing oil from being
sucked back into the apparatus. The valve’s functioning is not impaired by
gas ballast operation.
If the pump has to be shutdown, drain the oil flush out the pump with
fresh oil and fill in the required amount of clean oil (see § 5.4). Close the
connection ports. Special preservation or flushing oils do not need to be
used.
When the pump has been switched off due to over heating, initiated by the
motor or its temperature detector, the pump must be cooled down to the
ambient temperature, and must only be switched on again manually after
having eliminated the cause.
In order to prevent the pump from running up unexpectedly after a mains
power failure, the pump must be integrated in to the control sytem in such a
way that the pump can only be started by a manually operated switch. This
applies equally to emergency cut-off switches.
In case of switching processes in connection with a pump which has warmed
up under operation conditons, the pump must then not be directly switched
on again.
4.3 Ultimate pump pressure
If the values specified in the Technical Data are not reached in the apparatus,
measure the ultimate pressure directly at the pump’s intake port after
disconnecting the pump from the apparatus.
The ultimate pressure of non-condensable gases (partial pressure of air)
can only be measured with a compression vacuum gauge or a partial
pressure gauge. Precise measurements can only be obtained with calibrated
instruments.
Upon initial start-up, after prolonged idle periods or after an oil change, it
takes a while until the pump reaches the specified ultimate pressure. The
pump has to attain its operating temperature, and the pump oil has to be
degassed. We recommend operating the pump initially with the gas ballast
valve open.
The ultimate pressure depends on the pump temperature and the pump
oil used. The best ultimate pressures can be obtained at a low pump
temperature and by using the recommended oil types.
Caution