ITTSB.EU Blog Forum
Electrical Applications | Basic Power Analysis | Accessories | PSU | UPS evaluation | Battery analysis | CCTV camera system troubleshooting => Electrical Power Analysis & Technical discussion => Topic started by: Kiriakos GR on November 05, 2021, 06:28:12 PM
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APC SUA1000XL this is a UPS that at previously made tests, this show great delivery of perfect sinusoidal output.
Perfect sinusoidal output this translates to significantly stable delivery of volts output.
But in the end of the day every UPS this is an inverter.
DC/AC inverter this trying to do it best, but results will vary according the age of the technology in use.
I will punch some numbers from my test for you to review.
Test system this is PC computer just the main unit.
AC from grid: 235V 0.542mA 114 Watt PF=0.75 (PC computer main unit alone)
APC UPS load sensing 17,5 % in VA ( Sum of PC computer along peripherals)
Test starts .... Grid power OFF
AC from UPS : 233V 1.020A 90 Watt PF=0.40 (PC computer main unit alone)
APC UPS load sensing 23 % in VA ( Sum of PC computer along peripherals)
Power supply under test this is Corsair CX750 (the successful revision) :) 83% Efficiency at 15%of load. (highest efficiency 88.49% at 50% of load).
I am now wonder of what I did witnessed in this test?
It appears that the APC UPS while this indeed deliver perfect sinusoidal output, it circuit this delivering current its not that perfect, or clean, Power Factor damage by 45% this is indication that inverter losses are high, Efficiency score this is Low.
I am now using an budget power meter energy recorder, and I will not dare to speak of measurements with accuracy that I can trust.
But no matter the measuring error, 45% of lower PF this is a fact.
APC UPS load sensing this is UPS internal sensor / measuring of VA, PF reduction this increases VA consumption by 5.5% at this test setup.
Better conclusions they would be possible, if I had available an scientific grade power meter, but this can wait for now.