Ulvac EMP-20W, Instruction Manual

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ULVAC CRYOGENICS INCORPORATED 29
10. Automatic Transfer of Liquid Nitrogen
10.1 Inspections before starting automatic transfer
・
While liquid nitrogen is being dispensed, be sure to ventilate the room to
prevent a decrease in oxygen levels.
・
Never seal liquid nitrogen in the target devices.
・
Liquid nitrogen supply pipes reach extremely low temperature during and
right after the supply. Caution is also advised for the extremely cold gas
released from the nitrogen gas release port in the target container.
WARNING
Before starting automatic supply, make sure of the following:
(1) The level indicator cable is correctly connected between EMP-20W and the level
sensor of the target device.
(2) Liquid nitrogen supply tube is correctly connected between EMP-20W and the
container of the target device.
(3) The nitrogen gas exhaust port of the target device is open to the atmosphere.
10.2 Automatic transfer
(1) Turn ON the EMP-20W AUTO READY (Standby mode).
(2) Automatic transfer will start when the level sensor of the target device detects the
LN2 level is 25% or lower. If our level sensor is used, Automatic transfer can be started
forcibly by pressing AUTO SUPPLY button.
AUTO SUPPLY button lights up in white while automatic transfer is taking place.
(3) When the level sensor of the target device detects the LN2 level reaches 100%,
automatic transfer will be terminated. Automatic transfer will also be terminated when
the RUN/STOP or AUTO READY of EMP-20W are turned OFF, the LN2 level of
EMP-20W is 0%, or supply of nitrogen gas stops.
— Liquid nitrogen cannot be dispensed manually during automatic transfer.
— When the device is in standby mode by pressing AUTO READY button, manual
dispense of liquid nitrogen will be limited to 25%.
10.3 Time limit of automatic transfer
Automatic transfer is suspended when the fixed time (defaulted to 10 minutes) passes
from the start and the AUTO READY and the AUTO SUPPLY blink alternately.
Blinking will stop by pressing the AUTO READY button. Check the amount of liquid
nitrogen of the target dewar, and contact us when any abnormal conditions are found.
Please refer to the “Service Network” at the end of this manual for the contact detail.