American Power Conversion POWERCELL Power Supply User Manual


 
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3.0 Installation
3.6 Connecting equipment to the PowerCell (continued)
requirement of your equipment is 50% greater than the capacity of the UPS!
3.6.5 Once all power requirement figures have been converted to VA units and
added together, simply determine whether the power requirements of your
equipment is less than or equal to the capacity of your PowerCell. If this is not
the case, then it must be decided which equipment should be left unprotected by
the UPS. Many times, the system printer may be left unprotected. Print jobs lost
in the event of utility failure can always be re-queued. See section 3.8 covering
overloads.
3.6.6 An example of how to determine the power requirements of a computer
system is given below.
Example - labels found at system equipment rear panels
The power requirements of the example computer, monitor and external tape
drive may be calculated as follows:
Computer VA = 120 x 2 A = 240 VA
Monitor VA = 100 x 1.4 = 140 VA
Tape Drive VA = 120 x 1 A = 120 VA
_______________
Total = 500 VA
In this example, a UPS with at least 500 VA capacity can be employed to protect
the computer, monitor and external tape drive. However, a UPS with somewhat
lower capacity may still be used if the following test for proper operation is
successful.