Eppendorf LN2 Backup System - Manual (Page 30)

Technical data
New Brunswick LN2 Back-up System
English (EN)
30
9.6 Ambient conditions
9.6.1 Device operating environment
9.7 Gas Consumption
The consumption of gas is very difficult to specify because it is dependent on the operating conditions.
Gas consumption is affected by several factors. Consumption increases with:
• An increase in ambient temperature
• Increasing age of freezer
• Increasing age of door or lid seal
• A colder temperature set on the device
• Frequent opening of door or lid
We highly recommend that the user decide, prior to full operation, what temperature conditions the backup
unit should maintain. The user should then install the system, switch the freezer off, and record the time it
takes for the LN
2
Dewar to empty while the system maintains the desired temperature. This precaution will
enable the user to select the Dewar size best suited to providing the degree of protection required. As a
guide, the following chart can be used to calculate consumption:
Altitude Up to 2000 m
Minimum ambient temperature 5 °C
Maximum ambient temperature 40 °C
Maximum humidity at 31 °C 80 %
Maximum humidity at 40 °C 50 %
Pollution degree 2