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ULVAC CRYOGENICS INCORPORATED
10. Automatic Transfer of Liquid Nitrogen
10.1 Inspections before starting automatic transfer
Before starting automatic transfer, make sure of the following:
(1) The level indicator cable is properly connected between EMP-14A and the level
sensor of the target device.
(2) Liquid nitrogen supply tube is properly connected between EMP-14A and the
target dewar.
(3) The nitrogen gas exhaust port of the target dewar is open to the atmosphere.
10.2 Automatic transfer
(1) Turn ON the EMP-14A AUTO READY (Standby mode).
(2) Automatic transfer will start when the level sensor detects the LN
2
level is 25%
or lower. When our level sensor is used, automatic transfer can be started
forcibly by pressing AUTO SUPPLY button. AUTO SUPPLY button lights white
while transfer is taking place.
(3) When the level sensor of the target device detects the LN
2
level reaches 100%,
transfer will be terminated. Automatic transfer will also be terminated when the
RUN/STOP or AUTO READY of EMP14A are turned OFF, the LN
2
level of
EMP-14A is 0%, or supply of nitrogen gas stops.
Liquid nitrogen cannot be dispensed manually during automatic transfer.
When the EMP-14A is in standby for automatic transfer 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 fixed time (defaulted to 10 minutes) passes
from when the transfer begins, and the AUTO READY and the AUTO SUPPLY blink
alternately. Blinking stops by pressing the AUTO READY button. Check the liquid
nitrogen level in the target dewar, and contact us when any unusual conditions are
found.
・
While liquid nitrogen is being transferred, make sure to ventilate the room to
prevent 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 transfer. Caution is also advised for the extremely cold gas
released from the nitrogen gas release port in the target dewar.
WARNING
