Wall Charger tripping adjacent Breaker

[golferguy]

It looks like the breaker melted at the bus bar connection, so I'm wondering whether the exposed bus bar there had become weathered/corroded/dirty over the years. I'm surprised that the 60-amp breaker didn't trip thermally if it was radiating enough heat to trip the GFCI breaker next to it!

Glad you caught it!

That is my thought too. Wire connections did not show excessive heat but buss bar connection did. I think it is odd that Electric Panels are outdoors but if that is the local code, so be it.

I have a whole home generator. When the transfer switch was installed I demanded it go in the garage, not outside which is allowed here. Electrician had a fit until I showed him the spec on the transfer switch housing. It is spec'd to 40 mph winds. The purpose of my generator is for Hurricanes. 40mph ha!
It is inside the garage and after 10 years looks like new.

 

[tewest86]

It looks like the breaker melted at the bus bar connection, so I'm wondering whether the exposed bus bar there had become weathered/corroded/dirty over the years. I'm surprised that the 60-amp breaker didn't trip thermally if it was radiating enough heat to trip the GFCI breaker next to it!

Glad you caught it!

It never tripped the 60 amp. Can a breaker just melt away and never trip?

 

[thefisch]

It never tripped the 60 amp. Can a breaker just melt away and never trip?

Yeah, a faulty breaker can. I understand you suspect the panel but this could be a faulty breaker situation.

 

[tewest86]

Yeah, a faulty breaker can. I understand you suspect the panel but this could be a faulty breaker situation.

My concern is how do you know if a breaker is faulty until it’s too late? I’ve found other Wall charger installs where the breaker melted.

 

[GreenCoffee]

My concern is how do you know if a breaker is faulty until it’s too late? I’ve found other Wall charger installs where the breaker melted.

I doubt it is the panel or the breaker, I have seen the problem I suggested it could be earlier where a substantial nick in the wire or a loose wire can cause overheating of the connection and melting of the breaker without tripping it.

 

[thefisch]

My concern is how do you know if a breaker is faulty until it’s too late? I’ve found other Wall charger installs where the breaker melted.

All breakers will fail eventually, but out of the box you'd look for no play in the switch mechanism and high temperature especially given the continuous load demand of these chargers. Given their sacrificial nature, too often breakers are blamed when there's missed underlying problem such as what @GreenCoffee suggested below.

I doubt it is the panel or the breaker, I have seen the problem I suggested it could be earlier where a substantial nick in the wire or a loose wire can cause overheating of the connection and melting of the breaker without tripping it.

How confident are you in this electrician? I just wonder if blaming the panel is an easy out for them especially if they left a wiring issue (nicked, loose, etc.). I assume wiring and breaker issues would be on their dime since they just installed and may offer some labor and parts guarantee for new work. But they shift blame to the panel then it's not their dime. However you decide to handle, you may want the wiring replaced in case that was damaged from the temps or the cause.

 

[GreenCoffee]

All breakers will fail eventually, but out of the box you'd look for no play in the switch mechanism and high temperature especially given the continuous load demand of these chargers. Given their sacrificial nature, too often breakers are blamed when there's missed underlying problem such as what @GreenCoffee suggested below.


How confident are you in this electrician? I just wonder if blaming the panel is an easy out for them especially if they left a wiring issue (nicked, loose, etc.). I assume wiring and breaker issues would be on their dime since they just installed and may offer some labor and parts guarantee for new work. But they shift blame to the panel then it's not their dime. However you decide to handle, you may want the wiring replaced in case that was damaged from the temps or the cause.

Also when the OP posted a picture I did note that the insulation on one of the conductors had electrical tape on it, very suspect.

 

[tewest86]

I doubt it is the panel or the breaker, I have seen the problem I suggested it could be earlier where a substantial nick in the wire or a loose wire can cause overheating of the connection and melting of the breaker without tripping it.

There is no Nick in the wire. Removing the tape shows no Nick. No wire was exposed anywhere. I pulled the wire to check today. I will get the wire replaced or pull it myself.

 

[GreenCoffee]

There is no Nick in the wire. Removing the tape shows no Nick. No wire was exposed anywhere. I pulled the wire to check today. I will get the wire replaced or pull it myself.

That rules out that then, I assume that the connections at the breaker end were tight as well then?
It is possible that the new breaker was a faulty one, It is a baffling situation for sure.

 

[tewest86]

Also, breaker didn’t melt on conducts side. We

That rules out that then, I assume that the connections at the breaker end were tight as well I’ll then?st
It is possible that the new breaker was a faulty one, It is a baffling situation for sure.

it baffles me. I pulled wire myself to check and no nicks that exposed wire strand. Insulation still intact. With the new panel, I’m going to keep wall charger at 50 amps. I can sleep better knowing that. Most destination chargers I’ve used were less than 10 kWh.

 

[GreenCoffee]

Also, breaker didn’t melt on conducts side. We

it baffles me. I pulled wire myself to check and no nicks that exposed wire strand. Insulation still intact. With the new panel, I’m going to keep wall charger at 50 amps. I can sleep better knowing that. Most destination chargers I’ve used were less than 10 kWh.

So just one last attempt to explain what could have been the problem, did you look closely at the area of stripped insulation, most nicks occur at the line where the tool used to strip the wire comes in contact right at the edge of the stripped insulation, I know im probably beating a dead horse here but I just cannot figure out what would have caused this?

In this low res photo I cropped of a site that explains how to properly strip heavy gauge wire it appears that almost every outside strand has been nicked deeply on the white insulated wire and the red one looks to be missing some strands, this is the type of problem that can cause overheating by limiting the ampacity of the wire, I'm not saying you have this I just cannot figure out anything else!

 

[tewest86]

So just one last attempt to explain what could have been the problem, did you look closely at the area of stripped insulation, most nicks occur at the line where the tool used to strip the wire comes in contact right at the edge of the stripped insulation, I know im probably beating a dead horse here but I just cannot figure out what would have caused this?

In this low res photo I cropped of a site that explains how to properly strip heavy gauge wire it appears that almost every outside strand has been nicked deeply on the white insulated wire and the red one looks to be missing some strands, this is the type of problem that can cause overheating by limiting the ampacity of the wire, I'm not saying you have this I just cannot figure out anything else!

I will look closely at this and check. I removed the wire from the conduit to investigate. My other is when charging the Model X, I didn’t have one issue. I didn’t get the crazy temps till I hooked up the amodel Y. That should have no bearing. Temps on the breaker did go up till I hooked up the Y.

I’m an Engineer by day that spends a lot of time investigating failures so I’m deeply invested now. I like to know “WHY”.

 

[davewill]

I will look closely at this and check. I removed the wire from the conduit to investigate. My other is when charging the Model X, I didn’t have one issue. I didn’t get the crazy temps till I hooked up the amodel Y. That should have no bearing. Temps on the breaker did go up till I hooked up the Y.

I’m an Engineer by day that spends a lot of time investigating failures so I’m deeply invested now. I like to know “WHY”.

Of course, the breaker may have been getting hot, but not yet affecting the adjacent breaker. How did the contacts on the busbars in the panel look? Any corrosion? Was the breaker moved, replaced or in any way disturbed close to the time it started failing?

 

[thefisch]

Also when the OP posted a picture I did note that the insulation on one of the conductors had electrical tape on it, very suspect.

That was a good catch even though OP said the wire wasn't nicked under the tape. Outside of phase taping to identify the wires, seeing tape in a panel is worthy of investigating.

There is no Nick in the wire. Removing the tape shows no Nick. No wire was exposed anywhere. I pulled the wire to check today. I will get the wire replaced or pull it myself.

How did the terminal connections seem when you removed the wires? Were they hard to unscrew indicating they were well torqued down? Any carbon marking at the terminals (that didn't melt)?

I will look closely at this and check. I removed the wire from the conduit to investigate. My other is when charging the Model X, I didn’t have one issue. I didn’t get the crazy temps till I hooked up the amodel Y. That should have no bearing. Temps on the breaker did go up till I hooked up the Y.

I’m an Engineer by day that spends a lot of time investigating failures so I’m deeply invested now. I like to know “WHY”.

What were the amps set to in the X compared to the Y? Could be a difference in power draw.

We are all with you on wanting to know why. Do you have photos of the bus bar from before install and then after the melted breaker was removed? Just curious to see the condition of that.

When I installed the breaker in my panel I had the option of placing it lower than other breakers since I had 5 open spots on each side. Thought that might be better for heat dissipation. But I opted to install in the next slots down as it would be easier to removed the knockouts. Now I am kind of regretting that decision.

 

[tewest86]

Of course, the breaker may have been getting hot, but not yet affecting the adjacent breaker. How did the contacts on the busbars in the panel look? Any corrosion? Was the breaker moved, replaced or in any way disturbed close to the time it started failing?

So remember panel is original to the house which is 31 yrs old. Panel is outside in Tx heat and facing the west. The afternoon sun cooks my panel.

Once 60 amp breaker was installed, it was never touched again.

 

[tewest86]

That was a good catch even though OP said the wire wasn't nicked under the tape. Outside of phase taping to identify the wires, seeing tape in a panel is worthy of investigating.

How did the terminal connections seem when you removed the wires? Were they hard to unscrew indicating they were well torqued down? Any carbon marking at the terminals (that didn't melt)?

What were the amps set to in the X compared to the Y? Could be a difference in power draw.

We are all with you on wanting to know why. Do you have photos of the bus bar from before install and then after the melted breaker was removed? Just curious to see the condition of that.

When I installed the breaker in my panel I had the option of placing it lower than other breakers since I had 5 open spots on each side. Thought that might be better for heat dissipation. But I opted to install in the next slots down as it would be easier to removed the knockouts. Now I am kind of regretting that decision.

Wire were hard to unscrew. I actually played around with charging X at 60 and 50 amps to take temps. Temps never exceeded 120 degrees. Bus bar is in a 31 yr old panel that sits outside.

L1/L2 were #6 awg THHN and ground was #10 awg THHN.

screws were tight. (No torqywrench to verify).

 

[qdeathstar]

Time for a new panel, cutler hammer ch best bet.

 

[tewest86]

Time for a new panel, cutler hammer ch best bet.

This is my replacement panel. He told me it’s Eaton which is Cutler Hammer.

 

[thefisch]

This is my replacement panel. He told me it’s Eaton which is Cutler Hammer.

Homes in my neighborhood were built with the CH panels and they've been solid.

Wire were hard to unscrew. I actually played around with charging X at 60 and 50 amps to take temps. Temps never exceeded 120 degrees. Bus bar is in a 31 yr old panel that sits outside.

L1/L2 were #6 awg THHN and ground was #10 awg THHN.

screws were tight. (No torqywrench to verify).

The wiring sounds good then. Maybe it was the breaker or the panel, but either way after a breaker melts you probably have to replace the panel due to damage.

How did you get the X to charge at 50 or 60 amps on this circuit? Which charger do you have?

 

[tewest86]

Homes in my neighborhood were built with the CH panels and they've been solid.

The wiring sounds good then. Maybe it was the breaker or the panel, but either way after a breaker melts you probably have to replace the panel due to damage.

How did you get the X to charge at 50 or 60 amps on this circuit? Which charger do you have?

I meant 48 and 40 amps. I was referring to the breaker size.