3Com Prestige Series Power Supply User Manual


 
Introduction
2
Powerware
®
Prestige Series Installation and Operator’s Manual for IBM Applications (3000 VA) Uncontrolled Copy
UPS Model and Battery Configurations
This UPS is designed to work with single-phase, three-wire, AC power
sources. There are two important considerations when selecting the UPS
model and battery configuration to properly safeguard your equipment:
Load requirements
Battery times
Load Requirements
The load is the equipment to be protected by the UPS. Select the UPS
model that meets the power consumption requirements of the load in
volt-amperes (VA). The total load VA should not exceed the UPS VA
rating. To determine the total load requirements:
1. Obtain the load ratings from either the nameplate or operator’s
manual of the equipment to be protected by the UPS. The
ratings are listed in either watts (W), amperes or amperes
max (A), or volt-amperes.
2. If the rating is in watts, multiply by 1.4 to obtain the VA
requirement (this is the typical relationship between watts and
volt-ampere ratings in most computing equipment). However,
in some new computing equipment, the power supply is
power-factor corrected and the watts rating equals the VA
requirement. Check with the manufacturer to determine
applicability.
If the rating is in amperes or amperes max, multiply by the
input voltage to obtain the VA requirement.
NOTE For the load ratings of AS/400 models and attachable devices, see Chapter 9 of
“AS/400 Physical Planning Reference,” SC41-5109.
3. Add all of the resultant VA ratings together to obtain the total
load requirements of the equipment to be protected (see
Figure 2). If the load consists of the power-factor corrected
supplies, it is recommended to use total watts for the load
requirements.