Ulvac DTU-20 Series, Инструкция по эксплуатации

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1-3. Protector (thermal protector)
This pump is fitted with an automatic reset thermal protection relay for overload protection. This
device shuts off the motor power supply circuit automatically to prevent burn-out if the motor
temperature rises due to a pump fault which prevents rotation, or if load becomes excessive.
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1-4. Gas Ballast Valve (important)
Standard equipment of this pump includes a gas ballast valve. This valve is effective when
absorbing condensable gas such as steam or solvent vapor. There are cases that ultimate
pressure of the pump becomes high after the condensable gas was absorbed as the condensable
gas is changed to liquid state and remains in the pump chamber.
When air is inhaling from the gas ballast valve just before of the compression process of the
pump, the condensable gas shall be exhausted with air via an exhaust valve without changing to
the liquid state. However, the condensable gas remains in the pump chamber if large quantity of
condensable gas is exhausted or after having exhausted condensable gas without opening a gas
ballast valve because of a limit in throughput capacity of condensable gas by the gas ballast valve
Confirm whether hazardous, explosive compound is generated or not before using the gas
ballast valve.
Temperature of the vacuum pump rises when operated. Do not touch
the location other than the valve when the gas ballast valve is
operating. Start operation after closing the gas ballast valve always.
When the gas ballast valve is used, it is generally considered that the
absorbed medium reacts in the pump and exhaust vent. On that
occasion, using equipment or facilities shall be damaged and there are
risk of personal injury and human life.
In case the gas ballast valve is left open when condensable gas is not
exhausting, power loss or rise of ultimate pressure shall be resulted.
Close the gas ballast valve when condensable gas is not exhausting.
See "Warning" (8) (9) on P. 06.
WARNING
See "Caution" (6) on P. 07.
CAUTION
Warning
Note