APC 420 user manual How to Determine On-battery Run Time, 1000 VA 1400 VA Load 650 VA

13. How to Determine On-battery Run Time

Knowing the on-battery run time of the UPS is an important part of UPS use, especially in situations where the protected device uses an operating system that requires some time to gracefully shut down.

1 . To calculate the on-battery run time first determine the total load protected by the UPS in Volt- Amps. Obtain load figures from either the labelling on the protected equipment or the accom- panying literature. For loads specified in watts, multiply the specified figure by 1.4. For loads specified in Amps, multiply the specified figure by 120. Note: For equipment that does not specify power consumption, use the estimated equipment load table below.

2 . Add the individual loads to determine the total load.

3 . Compare the total load of your system to the run time table below.

Estimated Equipment Loads

	Device			Load (VA)			Device			Load (VA)
External Modem			30			CD-ROM changer					250
External CD-ROM			60			Tower 486 server					300
10Base-T stacking hub			80			Tower Pentium server					350
Desktop 486 server			200			RAID array					400
Desktop Pentium server			250			Multiprocessor server					500
		Typical On-Battery Run Time Versus Load, in Minutes
Load	420 VA	650 VA		1000 VA	1400 VA		Load	650 VA	1000 VA		1400 VA
50 VA	41	90		167	306		500 VA	7.2	14		29
75 VA	27	64		125	236		550 VA	6.5	13		26
100 VA	21	49		98	190		600 VA	5.8	11		23
150 VA	14	29		64	133		700 VA	-	9		19
200 VA	10	22		47	99		800 VA	-	7.7		16
250 VA	7.5	17		35	74		900 VA	-	6.6		13
300 VA	6.2	14		27	60		1000 VA	-	5.8		11
350 VA	5.1	11		22	50		1200 VA	-	-		8.8
400 VA	4.3	9.3		19	42		1400 VA	-	-		7.2
450 VA	-	8.2		17	35

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