PSU w/o load causing SMT1500 to trip to battery?

[BillP]

I have a Corsair AX1200 PSU hooked up to a Surge Arrest Performance which is in turn attached to a SMT1500. There is nothing else powered by the SMT1500. The SMT1500 is on a 15A circuit with a few lights, a PC monitor and modest PC. The circuit is far from being taxed.

(1) When I turn on the PSU with NO HARDWARE attached to the PSU (I shorted the proper pins so I could start the PSU without a motherboard attached) my UPS will immediately jump to battery and the Surge Arrest will report a Ground Fault. This is the only PSU I've had this happen with.

(2) When the above occurs I've noticed the battery on the SMT1500 will drop from 100% to ~80% charge. Keep in mind there is nothing actually pulling a load from the PSU!

Any ideas what could be going on?

Thanks.

[BillP]

Does the PSU Make Any Buzzing Sounds When The Ups Is On Battery???

[upsguy_apc]

When I see "shorted pins" and then ground fault it makes me think you are probably doing something wrong.. Just a guess

[BillP]

Wwallender wrote:
Does the PSU Make Any Buzzing Sounds When The Ups Is On Battery???

None.

[BillP]

You're kidding right? This trick, for starting a PSU w/o a motherboard, has been around for ages and is even listed on most PSU manufacturer websites. You can even buy a 24 pin adapter that does this for you.

"Then, get a small piece of wire, paper clip, or suitable object and short the green pin and a black pin on the 24-pin connector on the power supply." - http://www.corsair.com/support/faq/power-supplies/

[Anonymous user]

It is an understandable mis-interpretation of what you said, I think. Since you've clarified that you are talking about using the remote turn-on feature of the power supply, I wouldn't think that is the issue here.

However - most ATX supplies require a minimum load to operate properly. Even the FAQ you linked to says that in a number of places. It is possible that your power supply is more picky than most and its no-load operation is disturbing your surge protector. There is also the possibility that the power supply is simply broken. Do you have something that you can use to provide a decent-sized load on the power supply? An old hard drive or motherboard should do nicely. In case there is something wrong with the power supply, I would suggest NOT testing with anything new / expensive / etc. until you verify that it is operating properly.

I should also point out that you're trying to use a 1200W power supply on a 980W UPS (the "1500" in SMT1500 means 1500VA, not 1500W). That's something to consider if you're going to use this combination to power your system once it is assembled.

Message was edited by: Terry Kennedy

[upsguy_apc]

Forget the UPS and Surge arrestor and plug the PSU into a GFCI outlet in your house... If your trick to power on the PSU trips the GFCI then you probably have a faulty PSU.

[BillP]

The computers power supply not need a minimum load to operate normally, He is shoring out the correct pins green+ground tha is what the mobo uses to turn it on and even tho it's a 1200 psu it will only pull the watts that the components are using so with no load it should draw 2-10 i have a 600 watt psu and it only draws 200 watts cuz all components only are Drawing 200 watts so don't say he's wrong because he obviously has more experience than you

Also Corisar Powersupplys Tend To Act Up On APC Upses So You. Might want to set up monitoring and find out why it's switching to battery

Sorry For Spelling I'm Typing This On An Iphone

Message was edited by: Wwallender

[BillP]

Yes Try What UpsGuy Said

[BillP · Accepted solution]

upsguy wrote:
Forget the UPS and Surge arrestor and plug the PSU into a GFCI outlet in your house... If your trick to power on the PSU trips the GFCI then you probably have a faulty PSU.

The GFCI did not trip.