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I have been experiencing flickering lights from time to time in the last few months. Now I am losing power to 4 circuits at once without the breakers being tripped. This is happening intermittently for several days now, maybe a couple of weeks as my children advise. I have checked the breakers and they seems to work fine. It has been hard to trouble shoot because I have not been home when this has happened. Or, by the time I got to the panel the power restore itself? However today I was home all day, so I removed the panel cover to be able to access it should the problem arise. When it did I ran to verify the breakers. all OK! When I took a reading of the "5" circuits that all lost power at the same time, I gor a reading of 24VAC at all of them? The rest of the circuite were reading 124VAC. When the power mysterious turned back on, the readings at the same 5 breakers was 119VAC. It should be noted that all the problem circuits are on one leg of the panel? But not all the circuits in said leg are failing, or maybe not demanding power at that time?

What could be causing this anomolie?? Thank-you

PS. Our Power Utility "Power Supplier" has change the outdoor power meters from an older type to a newer smart meter last fall.

8 Answers 8

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Sounds like you have a problem in your panel. How old is it? Sounds like it could be a split-buss panel and only the "lighting main" fed breaker are being affected.

In my strong opinion you need to have a qualified/real electrician (ie: NOT a "handyman") come out and check it. This is typically NOT a DIY fix.

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    Thank-you for your reply.This panel was installed in 1994 when we bought the house. It is a split-buss panel.
    – Don
    Jun 8, 2015 at 22:39
  • Boy, doesn't 1994 seem a little late (recent) for a split bus panel? ;-) Jun 8, 2015 at 23:32
  • Thank-you for comment, after last comment and further research online and review of panel, it is a normal panel.
    – Don
    Jun 9, 2015 at 0:42
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You sound like you have a good handle on testing. I like that you have traced the problem to the panel. If the breaker is putting out 24V at times and 120V at other times than there is a problem somewhere around there.

You have two legs in your panel (red wire and black wire). You have tested all the breakers in your panel and it seems like you are getting 24V on some and 120V on others. I understand you say that all the problem circuits are on the same leg. Are there other loads on that leg that are testing 120V and not 24V when the others are. It would be good to know if it is just those breakers or that entire leg that is having problems. If you need help on testing the legs (hot to ground) than let me know.

Otherwise if you are not having the issue right now and therefore cannot test that than I would take out a few of the breakers that seem to be trouble and switch them for a known good breaker. It could possibly be some bad breakers.

Are all the breakers close together? If they are it sounds like some heat might be causing problems, making the breaker not operate as usual. If this was a Federal/Pioneer panel I wouldn't be surprised if it was a bad breaker. They have a bad name for not tripping when they are supposed to. And maybe a breaker that will not trip is heating other breakers up.

I would also check the bus below the breakers. Does the bus that the breakers sit on look okay. I can't imagine there would be a problem there but it would be good to look at it just incase something happened that I cannot think about.

Remember to turn the breakers on first on any breaker you remove from the panel. Testing to make sure OV is on the breaker to ground when the breaker is off sounds like a good plan with these dodgy breakers. They might be hard to get out to. Wear safety glasses and turn off anything that will make you feel safer getting them out if they are "fused" on there from too much heat. Perhaps turning off the main breaker would be a good idea!

I can't see the power meter being the problem unless an entire leg is seeing 24V. Otherwise I am thinking breaker problems. But try to investigate if there is a reason they stopped working besides perhaps maybe ,like I said earlier, a breaker getting too hot because it's not working properly. Just do visual inspections.

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  • Thanks, The breakers are separate from each other. Will change breakers to see if it works. Lights intermittently flickering on these circuits? Tested surrounding breakers for sampling, and they measure 124VAC during and after the failures. Whereas the failing circuits measured 24VAC during and 119VAC after the failure? No visible damage or corrosion to Bus Bar, but would need to take remove the breaker as suggested. When the A/C unit turns on outside, I notice a flicker in the lights also. At least one side of the A/C 240V is on this suspect busbar where the several breakers are failing?
    – Don
    Jun 9, 2015 at 12:47
  • Generally large loads coming on and off can cause lights to flicker. Even new homes with energy efficient large loads still flicker. Kinda sucky I know. So it sounds like you got to the bottom of the AC flickering the lights... Now your other problem.... Jun 9, 2015 at 23:12
  • Hello Janessa, Thanks for the quick response. Yup the other problem, I have switched positions of two breakers on the same bus bar with two others to see what happens next? I did not find any evidence of arcing or corrosion when removing any of the breakers. Just want to see if using another And yes the lights still have a little flicker... is this in anyway dangerous? Also I took some readings when I returned home and every things was OK? Monitoring on going....
    – Don
    Jun 10, 2015 at 0:30
  • welll, 6AM this morning power cutout again. Ran down stairs and found the entire bus bar A powerless. Measure from the main coming in on the house side of the main and no power, measure the otheside bus bar B 124vac. NEXT STEPS?
    – Don
    Jun 10, 2015 at 10:07
  • I imagine the main breaker is the next logical process of elimination. When power cuts out, to measure on either side of the main breaker? If power exists on supply side and not on house side of main breaker in the panel, it should be that breaker causing me all these problems and require an electrcien and Power Utility to shut of power to the house from the meter to make repairs? If no power on either side then should be calling the supplier? Am I on the right track?
    – Don
    Jun 10, 2015 at 11:27
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One other possibility that I encountered once: the two wires carrying the two phases from the power pole to the two legs each had an inline fuse (about the size and shape of a thumb) outside the house, where the lines entered the service pipe. One of the fuses was going wonky, and causing lights to flicker on any circuit on that leg...

The fuses were sheltered by the overhang of the soffit, but they were somewhat exposed to snow/rain/moisture. When the utility came to check out my problem, the fuse was swollen and steaming slightly in the cool air. An easy diagnosis ...

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  • Well fokes, the electricien came and found that a crimp at the mass need changing. This was completed and off he went. Seeming fixinf the problem. However, 2 day later it started again?? Just so happens several neighbors were also calling elecetriciens to verfity the very same thing over a period of time. Then Saturday night the power supplier truck was parked outside my house with tier boom extended over the main connection. I ask what was going on and they said they had a bad jumper and it needed to be replaced.
    – Don
    Jun 15, 2015 at 15:09
  • Once this was done, I have had no more problems and neither has anyone else! So the Power supplier had several customers go thru the routine until enough complained before they checked their own system which was the route cause of the problem. Thanks for all your help and responses to help get to the route cause and eventual fix. :)
    – Don
    Jun 15, 2015 at 15:09
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I’ve had this experience, and the neutral at the main, had a corroded lug, and for some reason it would be in and out, but that was the culprit! The solution, a new meter base!

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I'd (very carefully) do the voltage measurement on the supply-side of the breaker both in normal, and abnormal, states.

Do this with the main breaker off - so your house wiring can't be affecting your measurement.

You are likely getting the odd-voltage-readings (the 24VAC) because your 240V appliances are back-feeding power from the "good" side to the bad side when the problem occurs.

If, with the breaker-off, you measure low voltage on one of the supply side "phases", then you should call your utility and start talking with them about it.

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    Thank-you, I am making arrangements to have an electricien come in ASAP to take over from here. Even if I was to verify the main breaker defective I would not attempt changing it. I measure the feed before and after the meter, which means I would have to go on the roof for the before and in the panel before the breaker for the house side.
    – Don
    Jun 10, 2015 at 17:16
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Picture is probably best to see make/mod/type to the panel & ckt otherwise we are sticking to guessing. My experience with my last similar problem=light flickering which eventually lead to power loss; problem found after tedious pain taking effort of localizing insulation stripped during the initial install/build. The outer jacket of the ROMEX cut and stripped from the base of the conduit to the panel inner side to the respective cb which has a 2 feet cut that at first glance it would be hard to see the bare copper if I didn't remove the black wire out of its cb tie then I would never see the damage. Problem fixed with a piece of 28 inch long heat shrink over the black wire = no more light flickering, case closed. Good luck!

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  • divide and conquer...do one ckt at a time. Voltages with AC is cut and dry 110-130vac is typical everything else is problematic. In this case, 24vac can be read from neutral/white to ground isn't strange because it should be zero in theory, but here the black/hot read 24vac this could mean it is dumping the load somewhereelse/shorted to a nail in the wall maybe???
    – hung ngo
    Dec 24, 2019 at 19:27
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    Hello, and welcome to Home Improvement. Thanks for the answer, but it's a little hard to understand; would you make it a bit clearer? And, you should probably take our tour so you'll know how best to contribute here. Dec 24, 2019 at 20:26
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I’m not an electrician, but I had a somewhat similar electrical problem with the fluorescent tube light fixture not working in our closet With switch on I measured low voltage. I replaced the ballast and it works fine. Could be you have some florescent lights on that circuit that has a bad ballast causing low voltage but not tripping breakers.

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I ended up here on this thread due to similar symptoms - occasional flicker of lights , not tied to load demands from within the house or windy weather outside. Yesterday morning woke up to the power off in the whole house, except one or two circuits (!) The hallway lights worked, and one plug in the kitchen (for the coffee maker thank god). I went to the panel and no breakers were tripped. I called the power company , they came and immediately noticed the connectors at the top of my mast were weathered and ‘burned back’ , so they changed two of the three. They also swapped my meter on a just to eliminate another possible culprit. When power was re-applied, still no lights in the house. One of the crew came in and cycled the main breaker and there was a spark as it connected, and the power did come on. He said “that’s the problem right there” (the main breakers at the top of my panel) My electrician friend came over and ,with the meter off outside, pulled the main breakers off and cleaned the contacts with very fine sandpaper and some deoxidizer gunk that went right on the contacts of the breaker. That helped but didn’t fix the breaker. It was showing signed of oxidaztion and arcing. This panel has push-on breakers. It’s a siemens with two 125amp mains. Not sure if that is uncommon or not but the way he said it makes me think maybe. (New in 2000)

Anyhow new main breaker getting installed today. Just posting this for the next guy. (Any further news I’ll let you know)

Cheers.

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    This is good information and is a broad scope trouble shooting guide but doesn't answer the OP's question, which is five years old and probably won't be revisited.
    – JACK
    Nov 30, 2020 at 13:45
  • @jack the age of the question isn't important on SE sites. If someone provides "good information" years later, it's still good information. This may not be the cause of the OP's problem, but the situation described here produced similar symptoms so might be useful to other people that search for it.
    – Niall C.
    Nov 30, 2020 at 16:43
  • @NiallC. Agree with the age issue but was just bringing it up because the OP probably won't respond or select. It is still not an answer, good info but not an answer. Should be a comment.
    – JACK
    Nov 30, 2020 at 16:54
  • Sorry gang. It was only meant as a comment (or ‘commentary’ on the issue). I’m not here for ‘points’ or reputation per se. My rationale is this: if I had a problem and search revealed this (old) thread, then the next guy might search and arrive here too. I just wanted to add my details in case it helped the next guy, not to answer the OP. Cheers
    – First Last
    Dec 2, 2020 at 13:16
  • I’m back. The flickering never really went away. When I am near the panel as a flicker happens, I hear a “fzzt!” And that’s it. Over time I sometimes get a very worrisome 2sec dimming of the lights . And finally, sometimes the power to those circuits is totally cut off. - but it comes back on its own, or if a slam the mains off then in it seems to always restore things for a while. Going to show my electrician this thread and eliminate some possibilities. Brb(!)
    – First Last
    May 17, 2021 at 21:58

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