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The motor and pump become hot (temperature increase under non-load operation:
40 ℃ , temperature increase under high-load operation: 80 ℃ ) during
operation. There is a risk of burns. Never touch the motor or pump until they
have cooled down completely after the pump is stopped.
4.4 Operation in cold climates
In winter-season, when operating the pump in cold environment , 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.
If the pump does not restart, warm up the pump oil, or try to keep the pump within the operating
temperature for a little while and then turn on the power again.
When the pump stops after rotating for a few seconds, open leak valve (B) and continuous
operation may become possible. After the pump has warmed up, close leak valve (B) and return
to ordinary op
e
ration.
4.5 Backflow preventer
A backflow preventer is incorporated into the pump to prevent the oil from flowing back while
the pump is stopped.
The backflow preventer actuates in the case of an emergency including power failure. So, after
the pump is stopped due to a power failure, follow the procedures mentioned in “
4.3 Stopping
the operation
” to stop the operation.
① 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.
② If vacuum valve (A) is not closed, air may leak into the device side through
the pump increasing the pressure.
Caution
Note
