4
New Brunswick Scientific Co., Inc.
User’s Guide
1.3.5 LN
2
Supplies
Consult your local gas supplier for suitable LN
2
supplies. A low-pressure liquid
nitrogen storage Dewar (or other suitable storage tank) with a liquid
withdrawal port is required to properly utilize the cooling properties of the liquid
nitrogen. The liquid withdrawal port must have an adjustable valve with a
pressure gauge. The withdrawal pressure should be set to between 6 to 8 psig
(0.44 to 0.55 bar).
1.3.6 Electrical
Supply Requirements
Single phase, 100/240V, 50/60Hz, 1.0 Amp.
1.3.7 Fuses
The control unit input power socket is fitted with two fuses,
Live
and
Neutral
.
They are both 2-amp, 250-volt, 20mm ceramic T fuses (
see Section 5 for
replacement part numbers
).
1.3.8 Operating
Environment
The LN
2
backup system is designed for and tested to the CE/UL specifications
listed below:
•
Indoor use
•
Altitude up to 2000 M
•
Ambient temperature 5
o
C to 40
o
C
•
Maximum relative humidity 80% for temperature up to 31
o
C, decreasing
linearly to 50% relative humidity at 40
o
C
•
Power supply voltage fluctuations not to exceed
±
10% of nominal voltage
•
Installation category II
•
Pollution degree 2
