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I have 2 of these things: APC SmartUPS SC1500 (220v). My Proliant G5 DL380 PSUs seem to really hate them. This is what happens when UPS switches to battery (PSU2 is plugged into the SC1500):

iLo IML log:

</>hpiLO-> show system1/log1/record2
    description=System Power Supply: General Failure (Power Supply 2)

</>hpiLO-> show system1/log1/record3
    description=System Power Supplies Not Redundant

Every single time the SC1500 goes on battery, PSU goes dark then quickly back up again. If i plug PSU1 into the SC1500, same result.

I did some reading (really nice stuff BTW),

i have older SmartUPSes from APC (SU1400RMI2U) which either put out a better sine or have a faster transfer time because the PSUs in the DL380 acts very natural when they switch over to battery.

Aren't all SmartUPSes supposed to put out a clean sine?

I'm going to bring my Tektronix from home and check just how much of a sine is the SC1500's output really, but i was just wondering if this is a common problem with the SC1500 or i've been delivered some duds.

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Sounds like a defective UPS. You should call APC if it's under warranty. – Chris S Jun 6 '13 at 13:07
This isn't normal. You've answered your own question, though. Use a different UPS. – ewwhite Jun 6 '13 at 13:12
Oh man the other SC1500 is doing the same thing. Just tested. – evilSnobu Jun 6 '13 at 14:33

Well then, let me answer to my own question properly.

SC1500 --

Waveform Type: Stepped approximation to a sinewave

SUA1400 (the one that works) --

Waveform Type: Sine wave

I guess the PFC in the HP power supplies isn't very found of pixelated sine waves. Next time i'll be more careful with my power.

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