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4.3 Shut down operation
Close shut off valve (A), open pump vent valve (B), then turn off power switch
of the pump. If stopping the pump by no opening pump vent valve, the oil will
be filled inside the pump cylinder within several minutes. This may cause back
flowing oil to the vacuum vessel. For next operation, restarting the pump will
be difficult because of not so smooth rotation, thermal protector operating,
motor firing by over loading.
When stopping the pump operation by electric stoppage, close shut off valve (A)
quickly and then open pump vent valve (B).
Firing hazard. As the surface of the pump body is higher temperature(70
～80℃) during operation, do not touch it until cooled down after stopping
the pump.
・
To stop the pump, always close vacuum valve (A) and then open leak
valve (B). If this procedure is neglected, the pump oil fills the
cylinder, making restart difficult or causing damage to the pump. The
pump oil also may flow back to the vacuum chamber side.
・ If vacuum valve (A) is not closed, air may leak into the device side
through the pump increasing the pressure.
4.4 Start up procedures in cold climate
In winter-season, when operating the pump in cold environment or outdoor
especially, it will be difficult to start up the pump. It is called over-load
operation because of high viscosity of the pump oil at low temperature.
Warm up the pump oil, or repeatedly turn on and turn off the pump (several times
on-off operation) until motor starts rotation.
In the case of the pump stoppage after several second operating, continuous
operating will be possible by opening the pump vent valve. After warming up the
pump, close the pump vent valve, and operate normally.
