Print Page | Close Window

APC UPS Open Ground on Taichi X670E

Printed From:
Category: Technical Support
Forum Name: AMD Motherboards
Forum Description: Question about ASRock AMD motherboards
Printed Date: 04 Mar 2024 at 6:27am
Software Version: Web Wiz Forums 12.04 -

Topic: APC UPS Open Ground on Taichi X670E
Posted By: charles
Subject: APC UPS Open Ground on Taichi X670E
Date Posted: 25 Sep 2023 at 9:00am
I have an APC 1500-Pro UPS with a new battery.

During testing,I turn off the 120V circuit breaker to the UPS, and the battery beeps accordingly.

This does not turn off the 120V test lamp connected to the UPS Battery Backup outlets, but it does shutdown the computer.

I have since learned that turning off the power also breaks the UPS ground ??I get an open ground reading through my outlet tester when it's plugged into the UPS Battery Backup outlets.

In fact, I am unable to power on the computer through the UPS Battery Backup outlets unless I turn the breaker back on and the ground closes.

Is this due to the open ground? Is this normal?

Is there a way to solve this problem?

Thank you.

AMD Ryzen 9 7950X
Radeon RX 6600/6600 XT/6600M

Posted By: charles
Date Posted: 25 Sep 2023 at 9:29am
The two question marks in the fourth line are typos. They should be either a period or a colon. Sorry about that.

Posted By: charles
Date Posted: 25 Sep 2023 at 11:41am
Would just adding another ground wire between the computer and the UPS, like a T into the ground, work? I suppose this would be a lightening risk, but it can be fused. What's the deal?

And I have a whole house suppressor that I forgot to add to this comment.

Maybe the UPS unit is bad?? The previous battery was just causing shut offs, they were not even shutdowns lol.

Maybe I should just get another unit, it's about 7-8 years old.

Posted By: kerberos_20
Date Posted: 29 Sep 2023 at 4:44am
both ground or neutral lines should be unchanged independently whether breaker is turned on or off
if you get open ground with breaker off, then your breaker wiring is incorrect

-------------" rel="nofollow">" rel="nofollow - userbenchmark

Posted By: charles
Date Posted: 29 Sep 2023 at 5:19am
Thank you for your response.

The breaker wiring is correct. I get an open ground only from the back of the UPS device, and not from anywhere else on the residential branch circuit.

I have since purchased a new APC UPS, and I'm hoping this will resolve the issue.

Posted By: charles
Date Posted: 23 Oct 2023 at 12:55pm
Sorry if this comment is in the wrong place.

It seems the motherboard and computer will run from the battery alone, but it seems to shutdown if the power (breaker) is shut off.

It is a hard something, sleep, idk. But it definitely happens. However, if the breaker is off, and you boot from the battery alone, it is okay.

Posted By: charles
Date Posted: 23 Oct 2023 at 12:57pm
I have not tried this with a disconnected RJ12 yet.

Posted By: eccential
Date Posted: 23 Oct 2023 at 7:03pm
Ground is just ground. Not sure what you mean by "open ground."
Normally, Ground is tied to the Neutral at the source, as a standard practice.

Most quality UPS's also include isolating transformer, so the output Hot wire won't be directly connected to the input Hot wire.

As for Neutral wire, I've no idea. Never really studied it. But I guess it's entirely possible that UPS also supplies its own Neutral wire when on battery power. Basically 100% floating AC. This could actually make sense, in case the AC power has gone wanky and one of the UPS's job is to protect the equipment.

Ground should always be hard-wired to Ground, since it's a safety thing.

Does your PC shut off, or go through proper shutdown sequence, when you flip the breaker off?

If it shuts off immediately, I'd say your power supply is unable to keep the DC outputs going when there is a short glitch at the AC input side. You can try adjusting the UPS's sensitivity level to HIGH. All APC UPSs I know of have this control, but the adjustment depends on the model. HIGH setting can make it switch to battery more often, if AC power is even slightly inconsistent, but I think it might help with the glitch duration. Not sure.

Another possibility is that your power supply just doesn't handle the simulated AC power (stepped AC). I believe only the SMART UPS class outputs true sine wave output under battery, at least from APC brand. But I haven't kept up with the brand specifics in ages.

If it goes through software-initiated shutdown sequence, I'd think there's a software involved, whatever that may be.

Print Page | Close Window

Forum Software by Web Wiz Forums® version 12.04 -
Copyright ©2001-2021 Web Wiz Ltd. -