Barn breakers went bad after in house electric work

[OptionalStop]

This weekend I had the task of doing some basement electric work in my house and installing a few lights. While making some connections more than once I did it carefully with the circuits hot. In my barn, I have a sub panel fed with a 90 amp breaker off my main. About half of my GFCIs were lit red and could not reset. I opened up the sub panel and to my surprise the problem circuits had no 120v present at the breaker. Is it possible I damaged 3 of the breakers to the point of having to replace? I thought it was rare for them to go bad. None of them were tripped.

 

[Chuckster in NJ]

Reset the main breaker (off and on) to the barn....... If that doesn’t work call an electrical contractor.

 

[Terry D]

There has to be voltage to the GFCI's if they are lit red.

How are you testing the voltage

 

[alfredeneuman]

Turn the breakers OFF and recheck the connections you made carefully (especially the neutrals).
Working hot is a good way to send you off into never never land.

 

[wyliesdiesels]

There has to be voltage to the GFCI's if they are lit red.

How are you testing the voltage

bingo

they dont have batteries in them

also, dont know how one could damage breakers in an entirely different subpanel...

 

[OptionalStop]

There has to be voltage to the GFCI's if they are lit red.

How are you testing the voltage

I'm using one of those testers that just light up if 120v is present, so yes there is voltage but not enough for my light to indicate.

My connections are tight and well done, I took my time when I wired the building and did a nice job. I think I need to replace some of the breakers - if I bring one of the suspect circuits over to a breaker that is functioning properly, my GFCI works.

 

[Terry D]

I'm using one of those testers that just light up if 120v is present, so yes there is voltage but not enough for my light to indicate.

My connections are tight and well done, I took my time when I wired the building and did a nice job. I think I need to replace some of the breakers - if I bring one of the suspect circuits over to a breaker that is functioning properly, my GFCI works.

Get a meter that actually reads voltage. If your not comfortable doing this, hire someone. Read the voltage across you two mains in the sub panel. You should have something really close to 240 volts. If you dont have it, read the voltage at the breaker in your main panel feeding it.. If everything checks good. Read from one hot on your main in your sub to your neutral, You should have something close to 120 volts. If that checks out good, read the voltage at the suspected breaker, now go to one of the GCFI's thats wont reset. Confirm that the power coming in is wired to the line side screws. Read you voltage on these 2 screws, not the ground. You should have around 120 volts. You said that a red trip indicator was lit on the GFCI, there has to be power to it for that light to be on. What you are saying is making no sense. I dont see what you did in your basement, would cause anything to happen out in the subpanel.

 

[BigGarage]

I'm using one of those testers that just light up if 120v is present...

Get a meter that actually reads voltage.

Years ago my power to a detached garage stopped working. I tested it with the little tester that lights up if 120v or 240v is present. The red light lit up every time but nothing in the garage had power. I finally bought a multimeter and found the problem. The huge Oak tree next to the garage had almost but not quite cut off the buried line next to the garage leaving it just enough power to light the red light on the small tester. Getting a multimeter was one of the best moves I ever made, I should've had one anyway.

Dennis

 

[tdkkart]

I'm using one of those testers that just light up if 120v is present, so yes there is voltage but not enough for my light to indicate.

Hence the reason those testers belong right in the garbage. Only takes one time for it to not work before you're dead.

 

[wyliesdiesels]

I'm using one of those testers that just light up if 120v is present, so yes there is voltage but not enough for my light to indicate.

My connections are tight and well done, I took my time when I wired the building and did a nice job. I think I need to replace some of the breakers - if I bring one of the suspect circuits over to a breaker that is functioning properly, my GFCI works.

Wrong kid of tester to use for this.

Your GFCIs obviously have power since the red light is on.

Buy a wiggy or multi-meter and test with that.

 

[OptionalStop]

UPDATE: Looks like I have to dig up my cable. Using a borrowed multimeter, my 90 amp breaker inside my house main that feeds the shop reads 120v on both legs. At the shop, the 2 legs coming in are reading on one leg 120v, and the other is only 40v. Looks like the wire is dropping voltage somewhere on the way from the house to the shop. What else could I be forgetting to check?

I haven't done any disturbing or digging around the trench since it was buried 2 years ago. I used direct burial 2-2-2-4 wire 18" deep.

This *****.

 

[BillK]

Did you check the connection at the breakers ? Both in the house panel and at the shop ? If the screws have loosened you might be reading voltage at the screw but it is not getting transferred to the cable. Is it copper or aluminum cable ? I would turn the breakers off and loosen and re-tighten the screws.

 

[walta]

What are the chances that while you had the panel open the buried cable happened to fail?

The odds are it is some connection you disturbed.

I say don’t dig before you triple check the connections.


Walta

 

[OptionalStop]

It is aluminum cable. I did check the connections at both main breakers and they were tight - but I gave them more torque anyway. I am also checking the voltage on the wire itself, not at the breaker screw and getting the same readings.

I agree it's quite a coincidence for it to happen while I have my panel open for something else but I wasn't exactly messing around in there to disturb any wires or connections.

 

[wyliesdiesels]

This is why i put cable in conduit.

a rock couldve pierced the insulation

 

[TractorJeff]

This is why i put cable in conduit.

a rock couldve pierced the insulation

What are your weather conditions?
Freezing at night, thawing during the day?
The goofy weather we are having out here makes a lot of stuff move do to the unstable frost conditions.

 

[OptionalStop]

What are your weather conditions?
Freezing at night, thawing during the day?
The goofy weather we are having out here makes a lot of stuff move do to the unstable frost conditions.

Same conditions here recently, except I don't think the frost is going down to my 18" yet. Someone today mentioned I should try completely disconnecting my hots from the breaker at the shop and then test my voltage. I don't see why it would make a difference if it's connected to the breaker or not, but I will try it.

 

[Terry D]

There is a possibility that this feeder got damaged some how installing it, and it took 2 years for it to fail.

When you are reading voltage at the house, are you reading across the two lugs on the breaker, you should have something with in a few volts of 240

Is this feeder spliced somewhere, or is it continuous from breaker to sub panel.

How long of run is it. If the feeder is damaged underground, you might be able to use a cable tracer to pinpoint the break, and do a spot repair on it. The problem is this is not a common tool everyone has.

 

[OptionalStop]

There is a possibility that this feeder got damaged some how installing it, and it took 2 years for it to fail.

When you are reading voltage at the house, are you reading across the two lugs on the breaker, you should have something with in a few volts of 240

Is this feeder spliced somewhere, or is it continuous from breaker to sub panel.

How long of run is it. If the feeder is damaged underground, you might be able to use a cable tracer to pinpoint the break, and do a spot repair on it. The problem is this is not a common tool everyone has.

My breaker at the house is 90 amps with 2 120v wires going to the shop. Each one is reading correctly at 120v. My feeder is continuous and not spliced anywhere. It's about 150' run, and the electrical contractor here at work may have one of those tools, and hopefully be able to find something.

 

[Terry D]

My breaker at the house is 90 amps with 2 120v wires going to the shop. Each one is reading correctly at 120v. My feeder is continuous and not spliced anywhere. It's about 150' run, and the electrical contractor here at work may have one of those tools, and hopefully be able to find something.

To check it properly you have to read across the lugs on the breaker, not lug to neutral. You have to check for 240 volts first, not 120volt

Sent from my SM-G960U using The Garage Journal mobile app

 

[OptionalStop]

To check it properly you have to read across the lugs on the breaker, not lug to neutral. You have to check for 240 volts first, not 120volt

Sent from my SM-G960U using The Garage Journal mobile app

Thanks for the help. Do you mean to take my pos/neg probes on the meter and touch both lugs and it should read 240v?

 

[stickshift]

Thanks for the help. Do you mean to take my pos/neg probes on the meter and touch both lugs and it should read 240v?

Exactly. The two hot legs should be 180* out of phase with each other, so while each hot should be 120v to neutral, they should be 240v between each other. Same thing with every 2 pole breaker.

 

[PCustoms]

OP, can you post a picture of your main panel, showing the breaker and feed to the barn?

Cover off if you are comfortable.

 

[Terry D]

Thanks for the help. Do you mean to take my pos/neg probes on the meter and touch both lugs and it should read 240v?

Yes. You must check for 240 first at the breaker in your house panel

Sent from my SM-G960U using The Garage Journal mobile app

 

[OptionalStop]

My breaker is reading 240v across both lugs. At the shop, with the feeders disconnected from the breaker, I am now getting zero volts from one, and 120v on the other.

It's looking more and more like my cable has been damaged.

 

[Terry D]

My breaker is reading 240v across both lugs. At the shop, with the feeders disconnected from the breaker, I am now getting zero volts from one, and 120v on the other.

It's looking more and more like my cable has been damaged.

Unfortunately yes, sounds like you lost a leg to your shop. Just being a couple of years old on top of that really *****. You can probably find the failed spot with a cable tracer and do a spot repair. Let us know what route you take.

Sent from my SM-G960U using The Garage Journal mobile app

 

[PCustoms]

OP, can you post a picture of your main panel, showing the breaker and feed to the barn?

Cover off if you are comfortable.

I'll post this again.

Awfully coincidental that you loose a leg the same day you were playing around in the main panel....

Did you move any breakers in the main?

Move any wiring?

 

[510ebl]

Last ditch idea from a layperson before digging...pull the tandem breakers to the garage feed (in the main panel) and see if you have evidence of soot/carbon/arcing/corrosion.

Not that it was caused by your other work, but the breakers were disturbed at least a little when taking the dead front cover off and reinstalling same. Maybe revealing an existing concern?

 

[Terry D]

I'll post this again.

Awfully coincidental that you loose a leg the same day you were playing around in the main panel....

Did you move any breakers in the main?

Move any wiring?

He wasn't playing in the main panel. He said he did the work hot.

Plus he checked the voltage at the breaker feeding the sub panel. He has 240 volts going to the shop, just not at the shop

Sent from my SM-G960U using The Garage Journal mobile app

 

[OptionalStop]

I'll post this again.

Awfully coincidental that you loose a leg the same day you were playing around in the main panel....

Did you move any breakers in the main?

Move any wiring?

I agree its coincidental but no, I didn't move any wires or breakers in the main. All I did was run down the box flipping breakers to find the circuit I needed to shut off. That, and wired a few lights with a hot circuit.

Here is my house main (I only installed the breaker, all other wiring is NOT my work!!):



Here is the sub panel at the shop that I wired entirely:

 

[Wrench97]

For shits and giggles swap the wires on the breaker in the house box then retest at the shop.

 

[OptionalStop]

For shits and giggles swap the wires on the breaker in the house box then retest at the shop.

You ask and I do. You might be on to something here. I swapped wires at the house breaker and the dead wire did not follow at the shop. WTH is going on here....

 

[PCustoms]

You ask and I do. You might be on to something here. I swapped wires at the house breaker and the dead wire did not follow at the shop. WTH is going on here....

Don't know yet, but for one you have a mix of breaker brands in that main panel....

Do you know what breakers control the lights you wired?

 

[AntonLargiader]

Nothing magic there. The bad wire is connected to a different hot but it’s still bad.

 

[OptionalStop]

Don't know yet, but for one you have a mix of breaker brands in that main panel....

Do you know what breakers control the lights you wired?

No, I don't. I can find out tomorrow if it's something to look at. I'm getting proper voltage off the breaker, unless there is something going on with my neutral. All connections are tight.

 

[PCustoms]

No, I don't. I can find out tomorrow if it's something to look at. I'm getting proper voltage off the breaker, unless there is something going on with my neutral. All connections are tight.

I misunderstood the post I quoted. Disregard my question

 

[510ebl]

Mixed up the neutral and one line at the garage sub?

Are the readings being taken with the subpanel breaker off?

 

[OptionalStop]

Mixed up the neutral and one line at the garage sub?

Are the readings being taken with the subpanel breaker off?

I haven't touched the wiring in two years. It's been working fine.
Yes, I've been doing it both ways.

I think it's important to note that when I first started troubleshooting this yesterday, I had 40-60 volts present on the line - today there is nothing. When this first happened my GFCIs had red trip lights on, now there is no power to them at all.

 

[PCustoms]

What brand is your main panel?

What did you wire for lights?

While I suppose having a feed suddenly go bad is possible, I can't see how that would trip a GFCI breaker. There's got to be something going on related to the work you did.

 

[OptionalStop]

What brand is your main panel?

What did you wire for lights?

While I suppose having a feed suddenly go bad is possible, I can't see how that would trip a GFCI breaker. There's got to be something going on related to the work you did.

General Electric

I put in 2 more pull string light fixtures in the laundry room. I used the same circuit that the existing light was on.