Introduction

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.

 

COMPUTER

 

 

MONITOR

 

EXTERNAL

 

 

 

 

 

 

MODEM

 

100 WATTS

 

 

2 AMPS

 

50 VA

 

 

 

 

 

 

 

100 WATTS x 1.4 = 140 VA

2 AMPERES x 120 = 240 VA

50 VA

or 1 AMPERE x 240 = 240 VA

 

 

 

 

140 VA + 240 VA + 50 VA = 430 VA (Total Load Requirements)

Figure 2. Volt-Amperes Calculation Example

If the total load requirements of the equipment exceeds the capacity of the UPS, you must either reduce the number of pieces of equipment, or use a UPS with a larger load capacity.

When deciding on which pieces of equipment to remove from the UPS, select equipment that has a lower priority for power protection. Computers, monitors, and modems typically have a higher priority because they could be processing or transmitting data when a power outage occurs.

Battery Times

During a power failure, the UPS battery supplies power to your equipment, providing time to complete computing activities prior to UPS shutdown. The duration of this time period is directly related to the UPS battery configuration. By adding battery cabinets (EXT models only), you can customize the UPS to provide enough battery time for normal processing activities.

The rating label on the UPS rear panel shows the model number. Model numbers with a “P2” are EXT units; numbers with “HV” are high voltage units (208 - 240V models). The following tables show the average battery times by product model.

Powerware® 9 Prestige Series User’s Guide (600 VA - 1800 VA) : www.powerware.com

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