House Power and Outlet question.

[Tarvaln]

I moved into a new place that was built in the 60's. I set up my UPS and PC everything powered on fine but I noticed my volts on the UPS were lower than at my previous place.

Old place 121 volts no matter what.
New place 119-120 PC off, 116-118 PC on

I was playing Rise of the Tomb Raider and then after an hour my UPS started to beep like I lost power. But none of the lights went off. Then my PC shut down.

I thought maybe the outlet was bad so, I replaced it and the other in the living room. I noticed on the one connect to my PC there are only 2 wires. One black, one white. On the other outlet there were four wires, 2 black and 2 white.

Would it make a difference to plug the UPS and PC into the other outlet?
Also, is there a way to get the volts back up to 121 if that even matters?

Thanks for reading all of this!

 

[Burpo]

Voltage isn't bad. That UPS needs a ground tho.

http://www.dummies.com/how-to/content/alternating-current-in-electronics-hot-neutral-and.html

 

[frowertr]

+/- 5% is pretty standard for 120 AC. So those voltage ranges are perfectly acceptable.

The outlet that has four wires is feeding another outlet(s) down stream. The one that just has the single black/white is the end of the string.

Not sure why your PC would shutdown if it's connected to an UPS with a working battery. Even if the voltage dropped low enough to kick your UPS into 'battery mode', the UPS would have kept your PC running through the brownout. That's the point of the UPS after all.

 

[UsandThem]

What UPS model do you have and what model power supply?

 

[Ketchup]

Maybe the battery in the UPS is going.

 

[Red Squirrel]

I'm thinking it's a coincidence and the UPS may be bad. I'd start with trying a new battery, some will do a self test and if it fails it actually shuts off.

119v is fine. Though I'm concerned you said 2 wires and not 3, or did you just not mention the ground? You do need to have a ground, if not I'd look at running one.

 

[frowertr]

If the house has old wiring then it's possible they didn't run a ground to the outlets. But, yeah, the ground is needed for surge protection as it shunts any over voltage to the ground.

I would think that the battery backup would be unaffected without an earth ground at the outlet.

What did the outlet box look like when you changed the outlet? Was it metal? Do you have a multimeter by any chance?

 

[Tarvaln]

@ UsandThem: UPS is a Cyberpower that can do 1350 va and 810 watts. Power supply is Seasonic 750 M12 Bronze.

@frowertr: The box did look metal and no I don't have a multimeter.

Is there a way for me to add a ground to these outlets?

 

[UsandThem]

@ UsandThem: UPS is a Cyberpower that can do 1350 va and 810 watts. Power supply is Seasonic 750 M12 Bronze.

@frowertr: The box did look metal and no I don't have a multimeter.

Is there a way for me to add a ground to these outlets?

How old is the UPS, and do you have the Cyberpower CP1350AVRLCD or the CP1350PFCLCD model? Your power supply has active PFC and might explain why your PC shut off when it switched to battery power.

If you plug a basic surge protector into the outlet, does the grounded light come on?

 

[Tarvaln]

UPS is a Cyberpower CST1300alu.
https://www.cyberpowersystems.com/products/ups/pc-battery-backup/cst1300alu

I got it about 3 years ago.

Yes, the grounded light does come on.

 

[frowertr]

Is the light telling you it's grounded or is it saying there is a ground fault and is not grounded?

Did the metal box have metal conduit attached with the wire coming out of the metal conduit? Or was it regular Romex wire pushed into the box? Trying to determine if the box is grounded through the breaker panel. It's unlikely they used metal conduit in residential however.

 

[LTC8K6]

http://www.homedepot.com/p/Receptacle-Tester-RT100/203195018

http://www.amazon.com/Power-Gear-50542-3-Wire-Receptacle/dp/B002LZTKIA

Get an outlet tester and check the outlet.

 

[UsandThem]

UPS is a Cyberpower CST1300alu.
https://www.cyberpowersystems.com/products/ups/pc-battery-backup/cst1300alu

I got it about 3 years ago.

Yes, the grounded light does come on.

I would first run a self-test on your UPS to make sure its batteries are still good.

You can do this by using Cyberpower's Power Panel software. If you don't have connected to your PC via USB or serial cable, you can turn off the breaker to that outlet.

You can do this with your PC connected or you can plug in another product, and see if continues to power them.

At your old location, did your PC ever run on battery power from the UPS?

 

[Tarvaln]

Tested the UPS and it test good. I have had it kick on twice at the old place due to a power outage in the area.

@frowertr: The light is on a surge protector I have and it just says grounded. I think it's a lie though.

 

[piasabird]

Older houses may have intermittent power or bad wiring inside the walls. May also not be grounded at all. You can put in a grounded plug and run the ground wire to a metal pipe that goes into the ground or to a grounding rod. You should not even run a computer without a well grounded plug.

Dont know about the UPS much. House power use to be just 110.

https://www.quora.com/Is-the-power-...r-120VAC-How-about-220-or-is-it-240-or-235VAC

I think the power tap to the mains may be able to be adjusted. It can be anywhere from 105 - 125. Often they may just estimate it at 115 service.

When power goes out over transmission lines there is some resistence and possible power loss depending how far your house is from the power sub-station.

Batteries get old overtime and they can be damaged from power surges and fail to hold a charge over time. I have seen the Large IT UPS act up at work. For instance a lightning strike or someone knocking over a power pole can cause a surge. Sometimes power surges can take out a refrigerator or other large appliance.

 

[bruceb]

What is likely happening is as mentioned one outlet (the one with 4 wires) is feeding the other one (by your computer). I would almost bet on a bad connection at the 4 wire outlet. You have an old house and the outlets are probably the originals. Replace both of them with new ones and be sure all the wires, especially where one feeds the other one are nice and clean. You can either restrip the wire if it is long enough or just use a piece of sandpaper to polish the copper before you reconnect it. Could also be a bad circuit breaker or loose wire at the main panel. Especially check the Neutral at the panel.

 

[Tarvaln]

So how do I run a ground to those outlets? I saw this video but it doesn't seem safe.
https://www.youtube.com/watch?v=lSGkp7kjF0c

He mentions that older houses have a metal box around the outlet and are ground with a line wrapping around the stud not sure if that is the case I have or if that's even safe. Also, how would I find that out? Magnets?

I'm just not sure what to do here. I don't think the landlord is going to spring to get the place rewired but I don't what my stuff to short out. Any ideas?

Thanks!

 

[westom]

Older houses may have intermittent power or bad wiring inside the walls. May also not be grounded at all. You can put in a grounded plug and run the ground wire to a metal pipe that goes into the ground or to a grounding rod. You should not even run a computer without a well grounded plug.

Existence of safety ground has no affect on a UPS or PC. That safety ground exists for human protection. It does nothing for transistor (ie surge) protection. It would not cause a shutdown.

Does that safety ground exist? Many will rewire receptacles using same uninformed reasoning that made so many bogus recommendation. A perfect example is to ground a receptacle to an earth rod or water pipe. That does nothing useful. It is a code violation. It does nothing to avert the OP's problem. It recommended when one does not even know what that safety ground must do. That ground is for safety. How it must be wired is defined by codes for human safety.

A three light outlet tester can detect some defect. But it cannot say a receptacle is properly wired. If a previous owner wired a safety ground prong to a neutral wire, then that tester falsely reports a properly wired receptacle.

One posted numbers. He accurately noted that 5% voltage change is normal voltage. Meanwhile, voltage can change so much that an incandescent bulb dims to 50% or doubles intensity. Even voltage changes that great are normal voltage for any computer.

BTW, normal voltage centers on 120 VAC.

Why did the UPS complain - apparently causing a PC to shutdown? Life expectancy of a UPS battery is 3 years. UPS can switchover to batteries due to many anomalies that are otherwise made irrelevant by a PC's PSU. Best test is to operate computer directly connected to AC mains. And power an incandescent bulb (ie 100 watts or larger) on the UPS to learn what that UPS is doing. For example, does the bulb dim to 50% intensity or less? Does bulb change intensity?

How to ground that outlet? Either a three wire cable must connect the breaker box to that receptacle. Or the receptacle must be replaced (or protected) by a GFCI. Code is quite specific. But again, ground is completely irrelevant to the original symptoms. Ground is for human safety.

 

[LTC8K6]

Buy the cheap outlet tester and check the outlets if you really think you need to.

If the surge protector says it's grounded, the UPS indicates no wiring fault, and the outlet checker indicates no wiring fault, then there's no wiring fault.

In fact, the the first two would be quite enough for me. There's no wiring fault. Your UPS has a red "WIRING FAULT" led that would be very obviously lit up if you had an outlet wiring problem.

Is that led on the ups lit or not?

Wiring Fault Indicator (red)
This LED indicator will illuminate to warn the user th
at a wiring problem exists, such as bad ground, missing gr
ound or reversed wiring. If
this is illuminated, disconnect all electrical equipment
from the outlet and have an electrician verify the outl
et is properly wired. The UPS will
not provide surge protection without being plugged in
to a grounded and properly wired wall outlet.

https://dl4jz3rbrsfum.cloudfront.net/documents/CyberPower_UM_CST1300ALU.pdf

 

[westom]

If the surge protector says it's grounded, the UPS indicates no wiring fault, and the outlet checker indicates no wiring fault, then there's no wiring fault.

If a receptacle is wired defectively (ie if neutral and safety ground prongs are connected together), then a surge protector will claim it is grounded, a UPS will indicate no wiring fault, and the outlet checker will claim the receptacle is good. Any yet the receptacle is clearly wired defectively. Too many do not understand basic wiring AND do not know what those 'testers' report.

BTW, that citation says "UPS will not provide surge protection without being plugged in to a grounded and properly wired wall outlet." UPS also will not provide effective protection if connected to a properly grounded wall receptacle. They simply forgot to mention that part.

Existence of safety ground does not affect operation of a UPS or PC. That ground is for and defined by something completely different - protection of human life.

 

[redzo]

I have encountered this a lot. Don't get offended, but it is wise to get rid of that simple issues first:

1. Make sure that the PC + display are plugged into the left power outlets!
https://www.cyberpowersystems.com/products/ups/pc-battery-backup/cst1300alu
When the power goes off, only the devices connected to the left power outlets stay on, the ones connected to the right should power off almost instantly.

2. Test if the UPS battery requires replacement!
Power on the PC and make sure that nothing important is running in the background or some unsaved work! Disconnect the UPS from the mains and check if the UPS is able to keep the PC alive when power goes off. If the PC shuts off instantly, then you probably have to replace the UPS battery.

Some other things worth mentioning,

When tomb rider runs, and especially if you own a beefy GPU, get ready for the UPS' battery to get depleted faster than usually as your PCs power consumption is quite high under this scenario.
Runtime at Full Load (min) is only 2 minutes as per manufacturer's specs, but this was 3 years ago when the 2 batteries were brand new.

 

[LTC8K6]

If a receptacle is wired defectively (ie if neutral and safety ground prongs are connected together), then a surge protector will claim it is grounded, a UPS will indicate no wiring fault, and the outlet checker will claim the receptacle is good. Any yet the receptacle is clearly wired defectively. Too many do not understand basic wiring AND do not know what those 'testers' report.

BTW, that citation says "UPS will not provide surge protection without being plugged in to a grounded and properly wired wall outlet." UPS also will not provide effective protection if connected to a properly grounded wall receptacle. They simply forgot to mention that part.

Existence of safety ground does not affect operation of a UPS or PC. That ground is for and defined by something completely different - protection of human life.

That has never been my experience. The UPS and outlet checkers I have used have always been correct when they showed a wiring fault.

Just had this happen at a friend's house in VA. UPS wiring fault light was on. Got an outlet checker, which showed a Hot/Neutral reverse. Sure enough when we tracked the wiring back, we found just that and corrected it.

The Neutral and Ground are supposed to be bonded together, aren't they? Typically at the end inside the breaker box?

In the US, anyway.

 

[bruceb]

If the house was wired using conduit (not likely due to cost) or using BX / Armored Cable then you will see a red bushing where the BX cable enters the box. BX is grounded at the main panel due to it's metal casing. You can test it with a Test Lamp. Go from one of the wires to the outlet and to the metal box. If it lights up correctly, the box is grounded. You can run a wire from a threaded hole in the box with a screw to the receptacle ground screw. Also in most cases, if the box is grounded and the receptacle is screwed down all the way, the ears will also make a decent ground. There is no other way to add a ground in other cases, short of pulling in new cables.

 

[frowertr]

As Westom suggests, installing a GFCI is done typically when you are wanting to replace a 2 wire receptacle. But I'm not sure that will satisfy the requirements of the surge suppressor. GFCIs are for people. I just don't know enough about how the suppressor shunts over voltage to the ground at the outlet to say if the GFCI is all it needs.

Ask your landlord to run you a new dedicated circuit just for your computer. It will be a hell of a lot cheaper to do that than an entire electrical overhaul for the house.

 

[westom]

That has never been my experience. The UPS and outlet checkers I have used have always been correct when they showed a wiring fault.

Because an outlet tester reports some wiring faults, that means it always reports wiring as good.? Of course not. I said it will report some wiring faults. But can also miss other wiring faults. That means it cannot report a receptacle as good.

Electricity is different at both ends of a wire. Neutral and safety ground must meet at the breaker box - where the circuit breaker to be tripped is located. Those wires must always remain separated everywhere else.

Never assume only from observation. Observation without first learning facts (ie how electricity works; what is required by code, etc) if how junk science gets promoted. Fundamental electrical concepts say why neutral and safety ground are electrically different at the receptacle. Use a meter (rather than a three light outlet tester) to learn of that difference.

bruceb also makes assumptions. Does not matter if conduit acts like a ground. Even code demands a safety ground wire must be inside that conduit. Otherwise a receptacle's safety ground is unreliable - insufficient for its human safety purpose. If conduit was a good ground, then those receptacles would have been originally installed with three prongs - not two.