BR breaker Melted on Bus side

[gpiggaz]

I am self installing a solar array, and yesterday I was in my Bryant ( Now Eaton) 225A 42 lug panel from 1987 installing what will become the back feed breaker to route the solar to the grid. I installed a 40A dual pole type BR breaker in the last slot- Right above that slot is another 40A dual pole type BR breaker that feeds the power to my EVSE. The maximum current that is drawn on that breaker is 32 amps per code- it was installed with the EVSE almost 10 years ago. It's been charging my cars ever since. Today, I plugged in the car and noticed there was no power at the EVSE. Did a little investigating and discovered that there was no power coming out of the breaker that feeds the EVSE, I cycled it thinking maybe I did something to trip it yesterday when installing the breaker below it. Still nothing, So I pulled the breaker out of the panel, and much to my surprise it shattered leaving it's lugs on the main bus bars. I immediately shut the main breaker off. And upon further investigation, the EVSE breaker was melted internally, right at the lugs that tie to the bus bar- obviously it had overheated somewhere along the line, It does't smell so it must have happened sometime back and was still making connection because it was still charging the car until today- I must have just jostled it just enough to cause it to open up. I've never seen a breaker melt like this before- I don't see any damage to the actual bus bar, so the breaker failed internally. I guess maybe expecting a 40 amp breaker to supply 32Amps for a few hours a day for 10 years might be too much to expect? Now I wonder if my backfeed from the solar system which will put about 25 amps for several hours a day into the bus bar might be problematic.

I pulled the new solar breaker out and moved it up to the EVSE location for now and will buy another 40A BR breaker tomorrow- I'm still in the middle of my installation, and haven't yet pulled the wires over to the main from the inverter(actually from the AC disconnect). Probably will do that tomorrow or later this week though. I did notice that there was some grease on the new breaker's lugs. and didn't notice any grease on the pieces of lug that I removed, but again, that breaker had been there almost 10 years.

FWIW I did make sure I torqued the screws on the breaker to 25in-lb for the number 8AWG THHW wire that is connected to them. (Per the info on the side of the breaker) Should I have re-stripped the wire? I can do that if it's necessary.

Any advice from anyone to prevent this from happening again? Or should I just consider that the breaker ( which was installed professionally about 10 years ago) was just bad. These breakers are very inexpensive at about $11 ea.

 

[Bert_]

Those are the cheapest breakers and panel available today. What you saw tends to happen with bigger loads. It shouldn't but it does.

 

[alfredeneuman]

Those are the cheapest breakers and panel available today. What you saw tends to happen with bigger loads. It shouldn't but it does.

^^^^^^^^^
NorCal calls it "Zinsco 2.0" and rightly so

 

[rlitman]

Those are the cheapest breakers and panel available today. What you saw tends to happen with bigger loads. It shouldn't but it does.

Meh. I've seen a Square D bolt down breaker melt out a section of a bus panel too. Stuff happens with every brand, and I wouldn't let such an anecdote spoil the reputation of a brand.

 

[Jim greengo]

I had a 2p 60br breaker used as a main melted on to the buss a couple weeks ago.
Funny thing was it still had 240 running through it.

 

[kylefitz]

I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******.

 

[dcg9381]

I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******.

That's a great question. Defective breaker comes to mind if you're measuring the amps right.


OP - you're at 80% for too long on a "cheap" breaker. Glad you caught it... Replace it and move on.
Verify your charge amperage too, 37 amps is an "odd" amperage - I know that some EVs can control this, but I'd back off a few amps from 80% on any breaker.

 

[alfredeneuman]

Meh. I've seen a Square D bolt down breaker melt out a section of a bus panel too. Stuff happens with every brand, and I wouldn't let such an anecdote spoil the reputation of a brand.

A bolt on breaker won't do that unless the screw(s) that connect to the bus are not properly torqued, as opposed to a stab in where the installer has no control over it.

 

[Dustball]

I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******.

If you already know you're exceeding the circuit rating, why not correct it rather than wait for something to happen?

 

[dave*99]

If you already know you're exceeding the circuit rating, why not correct it rather than wait for something to happen?

"Originally Posted by kylefitz View Post
I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******."


Sounds like that is exactly what he is doing - the last owner made the problem, he is fixing it.

 

[Bert_]

Meh. I've seen a Square D bolt down breaker melt out a section of a bus panel too. Stuff happens with every brand, and I wouldn't let such an anecdote spoil the reputation of a brand.

All the stab in breakers can do it. Certain brands have a tendency to do it more than others.

I've never seen a bolted breaker with a bad connection unless it was loose from the start

 

[wyliesdiesels]

I am self installing a solar array, and yesterday I was in my Bryant ( Now Eaton) 225A 42 lug panel from 1987 installing what will become the back feed breaker to route the solar to the grid. I installed a 40A dual pole type BR breaker in the last slot- Right above that slot is another 40A dual pole type BR breaker that feeds the power to my EVSE. The maximum current that is drawn on that breaker is 32 amps per code- it was installed with the EVSE almost 10 years ago. It's been charging my cars ever since. Today, I plugged in the car and noticed there was no power at the EVSE. Did a little investigating and discovered that there was no power coming out of the breaker that feeds the EVSE, I cycled it thinking maybe I did something to trip it yesterday when installing the breaker below it. Still nothing, So I pulled the breaker out of the panel, and much to my surprise it shattered leaving it's lugs on the main bus bars. I immediately shut the main breaker off. And upon further investigation, the EVSE breaker was melted internally, right at the lugs that tie to the bus bar- obviously it had overheated somewhere along the line, It does't smell so it must have happened sometime back and was still making connection because it was still charging the car until today- I must have just jostled it just enough to cause it to open up. I've never seen a breaker melt like this before- I don't see any damage to the actual bus bar, so the breaker failed internally. I guess maybe expecting a 40 amp breaker to supply 32Amps for a few hours a day for 10 years might be too much to expect? Now I wonder if my backfeed from the solar system which will put about 25 amps for several hours a day into the bus bar might be problematic.

I pulled the new solar breaker out and moved it up to the EVSE location for now and will buy another 40A BR breaker tomorrow- I'm still in the middle of my installation, and haven't yet pulled the wires over to the main from the inverter(actually from the AC disconnect). Probably will do that tomorrow or later this week though. I did notice that there was some grease on the new breaker's lugs. and didn't notice any grease on the pieces of lug that I removed, but again, that breaker had been there almost 10 years.

FWIW I did make sure I torqued the screws on the breaker to 25in-lb for the number 8AWG THHW wire that is connected to them. (Per the info on the side of the breaker) Should I have re-stripped the wire? I can do that if it's necessary.

Any advice from anyone to prevent this from happening again? Or should I just consider that the breaker ( which was installed professionally about 10 years ago) was just bad. These breakers are very inexpensive at about $11 ea.

you have a bryant/Eaton BR panel. those are known for this. Ive actually replaced many BR breakers that suffered the same fate. They have crappy connections on the buss bar stab

it didnt melt internally. instead it had a high resistant connection on the buss and this caused a huge amount of heat which radiated into the breaker case, causing the bakelite to weaken and disintegrate.

in terms of a breaker having 32a running through it for 10hrs a day is nothing. millions of breakers have that much current and more flowing through them 24hrs a day.

the issue you have here is a crappy panel and breaker brand...

I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******.

what is the brand of breaker? if its a zinsco or FPE, then thats your reason...

That's a great question. Defective breaker comes to mind if you're measuring the amps right.


OP - you're at 80% for too long on a "cheap" breaker. Glad you caught it... Replace it and move on.
Verify your charge amperage too, 37 amps is an "odd" amperage - I know that some EVs can control this, but I'd back off a few amps from 80% on any breaker.

he said 32a NOT 37a

 

[dcg9381]

he said 32a NOT 37a

I stand corrected, 80% of 40A = 32A... I'd target 30A full time max.

 

[kylefitz]

If you already know you're exceeding the circuit rating, why not correct it rather than wait for something to happen?

Working on it, there’s only so many hours in a day and I work on the road 330 days a year.

"Originally Posted by kylefitz View Post
I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******."


Sounds like that is exactly what he is doing - the last owner made the problem, he is fixing it.

Bingo.

you have a bryant/Eaton BR panel. those are known for this. Ive actually replaced many BR breakers that suffered the same fate. They have crappy connections on the buss bar stab

it didnt melt internally. instead it had a high resistant connection on the buss and this caused a huge amount of heat which radiated into the breaker case, causing the bakelite to weaken and disintegrate.

in terms of a breaker having 32a running through it for 10hrs a day is nothing. millions of breakers have that much current and more flowing through them 24hrs a day.

the issue you have here is a crappy panel and breaker brand...



what is the brand of breaker? if its a zinsco or FPE, then thats your reason...



he said 32a NOT 37a

I believe it’s an Eaton BR like the OP. It was in the shop when I purchased the home. I cleaned it up a bit, still need to fix a 14ga wire on a 20 amp breaker (just 2 led lights in the office), and pull some new wire for the compressor and a few outlets.

 

[gpiggaz]

Well, I bought a new 40A breaker today- I noticed it's terminals have some sort of grease on them, I hope that fixes the issue going forward- I'm concerned that the Solar feed is going to suffer a similar fate- I don't think I'm in a position to replace the whole panel. I guess I could try to "clean" (with the main off of course) the main bus bar, but that seems like it could be risky too what if I damage it - what would I clean it with? How would I know it's clean?

 

[wyliesdiesels]

You Cant really clean the buss bars or fix the pits. Most of them are plated and if you use any chemical or abrassive on it, you will strip the coating and make it worse.

Best thing you can do is replace the buss bars or replace the panel. There are retrofit kits available from Eaton

 

[gpiggaz]

You Cant really clean the buss bars or fix the pits. Most of them are plated and if you use any chemical or abrassive on it, you will strip the coating and make it worse.

Best thing you can do is replace the buss bars or replace the panel. There are retrofit kits available from Eaton

Wyliesdiesels, I was going to ask you if there were any alternatives - Replacing the bus bars sounds like an option. But of course that would require the house power to be pulled at the meter socket for some amount of time - that's not very attractive either. I'll dial the current down to the EVSE- it's a simple thing to do- I'm still worried about the Solar's input current though.

 

[Bert_]

If it looks damaged just put the new breaker on different part of the buss.

 

[gpiggaz]

So I just looked at the options for retrofit from Eaton- None of them state exterior panels- They are all for interior panels. I guess I'll have to live with this - no way I'm going to replace the panel - I haven't yet carefully examined the bus bar to see if it's pitted but I'm guessing it probably has some pitting since it's over 30 years old and is outside.

I can't move any of the breakers- The panel will now be full (all 42 spaces) when I put in the solar breaker.

 

[Bert_]

So I just looked at the options for retrofit from Eaton- None of them state exterior panels- They are all for interior panels. I guess I'll have to live with this - no way I'm going to replace the panel - I haven't yet carefully examined the bus bar to see if it's pitted but I'm guessing it probably has some pitting since it's over 30 years old and is outside.

I can't move any of the breakers- The panel will now be full (all 42 spaces) when I put in the solar breaker.

Put a couple lightly loaded circuits in the questionable spots. Put the bigger breaker in the good spots

 

[gpiggaz]

Bert, I'll look into that possibility Thanks.

 

[Dustball]

I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******.

If you already know you're exceeding the circuit rating, why not correct it rather than wait for something to happen?

"Originally Posted by kylefitz View Post
I wonder if that’s why I’ve been pulling 19 amps of lighting through a 15 amp breaker and never had a trip? I’m in the process of changing out the last owners *******."


Sounds like that is exactly what he is doing - the last owner made the problem, he is fixing it.

Working on it, there’s only so many hours in a day and I work on the road 330 days a year.

Bingo.

I stand by what I said. You know that have a hazardous situation with the previous owner's mess and you're running 19 amps on a 15 amp circuit yet you're using time as an excuse. Disconnect some of the lights to bring it under 15 amps until you're able to upgrade the wiring/split into multiple circuits.

 

[kylefitz]

I stand by what I said. You know that have a hazardous situation with the previous owner's mess and you're running 19 amps on a 15 amp circuit yet you're using time as an excuse. Disconnect some of the lights to bring it under 15 amps until you're able to upgrade the wiring/split into multiple circuits.

Currently I have abandoned the 14 gauge feed to that circuit, it’s buried in the wall and no longer hooked up at the panel. Of course my temporary solution of taking The two light circuits, combining them into a temporary cord end and plugging it into an extension cord plugged into a 20 amp circuit probably wouldn’t jive with you either. There is some thing about working in a 20° pole barn, with no lights and power tools, that sounds even less safe to me.

 

[reader2580]

It sounds like the OP doesn't really have enough space for the extra breaker needed for solar since one of the breaker spaces really should not be used for safety reasons. The 26% credit for solar can generally be extended to a panel upgrade if the upgrade is necessary to accommodate the solar install. I think this would qualify.

I replace the entire electrical service in my house in order to accommodate the additional panels I was adding. The line side tap I had was no longer big enough to handle the current. I replaced the meter base with one that has the capability to add additional terminals that can handle a 150 amp line side tap. A new meter base meant adding an exterior disconnect switch under 2020 code. This also meant replacing the main breaker panel as no easy way to separate grounds and neutrals in old panel.

 

[grounded-b]

I would put the biggest loads up near the Main breaker. This way the entire length of the bus, doesn't need to carry those heavy loads. Less heat build-up.

 

[Bert_]

I would put the biggest loads up near the Main breaker. This way the entire length of the bus, doesn't need to carry those heavy loads. Less heat build-up.

It really makes no difference.

 

[gpiggaz]

It sounds like the OP doesn't really have enough space for the extra breaker needed for solar since one of the breaker spaces really should not be used for safety reasons. The 26% credit for solar can generally be extended to a panel upgrade if the upgrade is necessary to accommodate the solar install. I think this would qualify.

I replace the entire electrical service in my house in order to accommodate the additional panels I was adding. The line side tap I had was no longer big enough to handle the current. I replaced the meter base with one that has the capability to add additional terminals that can handle a 150 amp line side tap. A new meter base meant adding an exterior disconnect switch under 2020 code. This also meant replacing the main breaker panel as no easy way to separate grounds and neutrals in old panel.

OP here- I've never seen a requirement to not use all the spaces in a panel. I guess I'll find out when it's inspected by not only the county but the power company next week. I'm almost done installing everything.

 

[gpiggaz]

I would put the biggest loads up near the Main breaker. This way the entire length of the bus, doesn't need to carry those heavy loads. Less heat build-up.

The bus bar is rated at 225A it's whole length. Moving the high current loads isn't possible without extending the wires too. Only requirement I've seen is to put the back feed breaker at the opposite end of the bus from the main, which is what I'm doing

 

[wyliesdiesels]

OP here- I've never seen a requirement to not use all the spaces in a panel. I guess I'll find out when it's inspected by not only the county but the power company next week. I'm almost done installing everything.

there is no such code mandating such