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Discussion Starter #1
Hi all got a good one we could you the collectives thoughts and ideas on. Scenario: Small Sq D homeline 6 ckt sub panel in a small apartment with breakers randomly turning off, not tripping. Utility thought it may be their end, after trouble shooting and running a recording they said it was customer side.
What we've tried-
Pulled apart every device, inspectected and remade each connection.
Isolated and checked each circuit including panel feed from main for direct shorts- hot to hot, hot to neutral, hot to ground none found.
Thermal scanned panel for hot spots- none found
Megged each wire all check ok.
Replaced Main Breaker, and branch circuit breakers.
Moved branch circuit wires from one side of panel to other side. swapped breakers around to different locations. Breakers still turning off on their own not tripping.
Replaced all GFCI's.
With no load the breakers will still turn themselves off. It has done it twice while we were standing there watching the panel. Called Sq. D, they said the breakers can't do what they're doing. Which I used to say the same myself. I stopped charging these folks long ago now I just need to know what it is. I have 35 years in this trade and my dad who retired with 50 used to tell me when I was an apprentice- "Troubleshooting electricity is never magic or a mystery, it's always the one simple thing you overlooked". HELP- what are we not seeing? Next step is a Priest and some sage!
 

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Welcome to the forum.

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We had a guy in a Starbucks or similar with a situation similar. We finally convinced him to set up covert video. Sure enough it was a rogue employee.
When you say it happened with you standing there, did you see it? Or were you and someone else there and it happened and they want you to believe they did not touch it?
Set up a video and then post a video of this happening with no human intervention.
Is there anything in the building other than apartments? Like a MRI facility?
 

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How many are GFCIs and AFCIs ?
Any regular breakers doing it ?
 

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Discussion Starter #5
Thanks guys- One of our guys was standing at the doorway talking with occupant when he heard the handles flip. He said there were no other people there other than small toddlers that couldn't reach. Landlord said they are good tenants with no beef. That's the first thing I thought was a disgruntled tenant. I also had him stomp on the floor at the panel and pound on the wall around it- nada. No other facilities other than 3 or 4 more apartments on same meter cluster. No gfci breakers or Arc fault breakers- standard Sq-D homeline breakers. One GFCI in kitchen, one in restroom.
 

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Are these the SQ D with trip window?
Are you sure it is not tripping and window is not showing it.
Remove breaker, turn it on then. Hold breaker in one hand and smack breakers stab end against palm of other hand.
Did the handle go to trip or off, and how hard did you have to smack it to change?
Most time this action will trip the breaker not turn it off.

Cowboy
 

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If the breaker is tripping/turning off on its own and not connected to a load it’s a bad breaker.
if you’ve moved this breaker and it keeps doing it on the new circuit, it’s the breaker.
If the original circuit trips the new breaker, it’s the circuit.

I had one single pole QOB do it even with it sitting on a bench.
 

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Couple of circuits shared by the neighbouring apartments ?

Time to set up monitoring on at least one of the trouble circuits.
 

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Hi all got a good one we could you the collectives thoughts and ideas on. Scenario: Small Sq D homeline 6 ckt sub panel in a small apartment with breakers randomly turning off, not tripping. Utility thought it may be their end, after trouble shooting and running a recording they said it was customer side.
What we've tried-
Pulled apart every device, inspectected and remade each connection.
Isolated and checked each circuit including panel feed from main for direct shorts- hot to hot, hot to neutral, hot to ground none found.
Thermal scanned panel for hot spots- none found
Megged each wire all check ok.
Replaced Main Breaker, and branch circuit breakers.
Moved branch circuit wires from one side of panel to other side. swapped breakers around to different locations. Breakers still turning off on their own not tripping.
Replaced all GFCI's.
With no load the breakers will still turn themselves off. It has done it twice while we were standing there watching the panel. Called Sq. D, they said the breakers can't do what they're doing. Which I used to say the same myself. I stopped charging these folks long ago now I just need to know what it is. I have 35 years in this trade and my dad who retired with 50 used to tell me when I was an apprentice- "Troubleshooting electricity is never magic or a mystery, it's always the one simple thing you overlooked". HELP- what are we not seeing? Next step is a Priest and some sage!
I like your dad's quote! Using the term GHOST may be appropriate in this case. :) The last time I experienced breakers turning themselves off was in a NEMA 3R panel... after racking my feeble brain on three different service calls I came up with the brilliant idea (Duh) of putting a padlock on the panel door. Yep, that solved the problem. Same kind of stuff I did when I was a teenager!
 

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Couple of circuits shared by the neighbouring apartments ?

Time to set up monitoring on at least one of the trouble circuits.
Good thought
Have the HO turn off circuit and wait for complaint, then have them back bill neighbor for electric bill and your time.
$$;) $$
 

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If the breaker is tripping/turning off on its own and not connected to a load it’s a bad breaker.
if you’ve moved this breaker and it keeps doing it on the new circuit, it’s the breaker.
If the original circuit trips the new breaker, it’s the circuit.

I had one single pole QOB do it even with it sitting on a bench.
Troubleshooting ghost problems 101. We all forgot to start back at basics.
 

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If the breaker is tripping/turning off on its own and not connected to a load it’s a bad breaker.
if you’ve moved this breaker and it keeps doing it on the new circuit, it’s the breaker.
If the original circuit trips the new breaker, it’s the circuit.

I had one single pole QOB do it even with it sitting on a bench.
I wonder if he knows the difference? You have a good point, because he doesn't mention changing out any of the circuit breakers. I have experienced the same tripping deal with QO's... they are very sensitive.
 

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Have you checked the condition of the subpanel? Any chance for debris floating around the hot bus bars? Maybe a loose screw causing intermittent shorts? Check condition of bus bar anyway.
 

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I had a similar situation recently. A 2 pole 50A for the range was burning up. A handy man wire it and cut several strands off the #6 cu to make to easier to fit in the breaker. The heat caused by that connection was destroying the 2 pole 50. The heat was also causing nearby breakers to heat up and lose the connection to the bus. Some would trip, some would just quit working. Thankfully it was copper bus and I caught it early enough that the bus wasn't ruined, only several breakers.
I shut off the main, used emery cloth to shine the copper bus and installed new breakers. I tightened every connection in the panel. That was 2 months ago and everything is still fine.
 

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I would use a gfci tester and trip the breakers on purpose to see if they are capable under a gfci fault of going all the way to off rather than tripped.

If they can then its sounds like a simple problem of gfci sharing wires. The problem is this will only show up when a load is present and its using more than 6 ma. A light dimmer, occupancy sensor, etc may be able to bug ground as a neutral on a gfci circuit and be just on the trip range but you are saying its always more then 1 breaker.
A receptacle with a live from one breaker and a neutral from a different gfci breaker will not trip until you plug in a load then both will trip together but it should always trip the same 2 breakers every time.
 

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Discussion Starter #16
Are these the SQ D with trip window?
Are you sure it is not tripping and window is not showing it.
Remove breaker, turn it on then. Hold breaker in one hand and smack breakers stab end against palm of other hand.
Did the handle go to trip or off, and how hard did you have to smack it to change?
Most time this action will trip the breaker not turn it off.

Cowboy
Handles go to off not center trip. These are Homeline (BR style) no trip window
 

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Discussion Starter #17
If the breaker is tripping/turning off on its own and not connected to a load it’s a bad breaker.
if you’ve moved this breaker and it keeps doing it on the new circuit, it’s the breaker.
If the original circuit trips the new breaker, it’s the circuit.

I had one single pole QOB do it even with it sitting on a bench.
We changed out all breakers (main and branch). We purposely did not terminate wire on one of the breakers. No trip but shutoff with the rest. Sq D factory folks asked that we video the panel - lol. They said what we have all said "Can't happen, someone is turning them off"
 

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We changed out all breakers (main and branch). We purposely did not terminate wire on one of the breakers. No trip but shutoff with the rest. Sq D factory folks asked that we video the panel - lol. They said what we have all said "Can't happen, someone is turning them off"
Cat?
 

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Discussion Starter #19
Good thought
Have the HO turn off circuit and wait for complaint, then have them back bill neighbor for electric bill and your time.
$$;) $$
Hmm maybe but how is it taking out the others? Plus, again their not tripping they are shutting off.
 
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