Fried 60A Circuit Breaker

[jpblincoln]

I have a Ford Connected 48A charger that I run at 42 amps. Over the past three years, I've fried two 60A Eaton Cutler-Hammer style circuit breakers. This time, I'm purchasing the actual Eaton brand, as I suspect the previous ones were Eaton CH clones. I also plan to reduce the current to 36 amps. When the breaker dies the blue charger light turns off, and there’s no 240V across the terminals. Has anyone else experienced similar issues?

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[phidauex]

It is possible for breakers to fail like anything else mechanical, but two in a row is suspicious. Do they look tripped, but won't reset?

Trying another model makes sense, breakers are supposed to work continuously, but most manufacturers know that a breaker will almost never be at its full continuous rating, so many aren't very robust for extended full power use.

 

[Scooby24]

Were they torqued to spec? That seems very odd they would fry if torqued to spec and had properly sized wiring. Did you go with Aluminum or Copper? Gauge?

 

[Maquis]

Look at the bus where the breaker attaches. If you see any discoloration, relocate the breaker to a new spot. And always use breakers listed as compatible on the box label.

 

[Tomm]

I would hire an electrician to take a look. I wired my own, but it works and has not fried the breaker. If it does, I will get an electrician.

 

[Scooby24]

When I installed mine (with an electrician friend) I bought a torque screwdriver to be sure both the breaker and the receptacle had the properly rated torque levels on the screws and I was legit SHOCKED at how much torque that actually was. My Receptacle is a Cooper (Now Eaton) 5754N which is phillips head screw and couldn't take as much as the Hubbell or Byrant but at 25 inch lbs, before I got the torque screwdriver out I thought I had torqued it enough...but not even close. It took a LOT more than I thought. Thought for sure I was stripping it.

Then when we got to the breaker, for 6awg it was 40 inch lbs. That felt like a hell of a lot.

For 60 amp I'm assuming you should have used 4 awg copper and that would have needed 45 inch lbs. If you used aluminum I think that would have had to be 3 awg, 50 inch lbs.

 

[jpblincoln]

#4 copper wire. I’ll make sure to torque the screws.

 

[AZBill]

I had had 60A breaker to my pool equipment sub panel melt down and fail several years ago. More recently had one leg of a 125A breaker going to my detached garage fail. Both were Eaton. Too much of this junk is poorly made in China.

 

[Old_Norm]

I use crimped ferrules with my wiring. But you need the proper tool to do the job correctly. As someone said earlier, you'll be surprised how fastening bare wire under set screws can be deceptive when you think they are tight. Ferrules avoid the stranded wire spreading as it us tightened. Here's the proper tool.
https://www.amazon.com/Preciva-0-08...aw+wire+crimping+pliers,tools,103&sr=1-1&th=1

 

[Mach-Lee]

I have a Ford Connected 48A charger that I run at 42 amps. Over the past three years, I've fried two 60A Eaton Cutler-Hammer style circuit breakers. This time, I'm purchasing the actual Eaton brand, as I suspect the previous ones were Eaton CH clones. I also plan to reduce the current to 36 amps. When the breaker dies the blue charger light turns off, and there’s no 240V across the terminals. Has anyone else experienced similar issues?

Where are you getting these breakers from? If you're buying them online for the cheapest price, there's a decent chance they're counterfeit. Always buy electrical devices from a brick and mortar store like Home Depot or trusted electrical supply houses. Type CH with the tan handles.

Like others say, you also need to check the bus bar the breaker stabs into. If that's damaged, then it will continue to cause overheating and further damage.

Torque the screws to spec, then loosen and torque them to spec again. This helps "settle" the strands and reduces loosening over time. If the copper is heat damaged, it needs to be cut back so fresh bright copper is exposed and used for the connection.

If it can't handle the full 48A all night long, something is wrong and needs investigating. Lowering the amperage is just a band-aid and should not be a long term fix.

 

[Adventureboy]

If it can't handle the full 48A all night long, something is wrong and needs investigating. Lowering the amperage is just a band-aid and should not be a long term fix.

^^^^ This ^^^^

I've had to replace 1 breaker in 3 years. 50A on 40A EVSE. Nothing wrong with the wiring or torque, it just gave up and wouldn't reset. The breaker was about 15 years old and had run my welder periodically. It didn't handle the constant power draw from an EVSE for more than a few months. Good brand name replacement from an electrical supply shop has been running daily now for 2.5 years across 2 EVs.

 

[ChasingCoral]

Open up the junction box where your EVSE is connected. Check for signs or loose wires or charred connections. If your EVSE is plugged in, check the connection of the plug in the receptacle.

 

[johnnycombo]

I have a ChargePoint hardwired and a 14-50 receptacle for my Grizzl-E mini. With the recommended wire at ”that time” my ChargePoint was set to 48 amps and the 14-50 limited to 40amps charging. On doing research for installing an industrial duty 14-50 , I also found the romex wire has also been downgraded for evse use. So instead of rewiring I lowered my breaker amps on both circuits and my ChargePoint is now set at 40amps and the Grizzl-E 32amps with new industrial 14-50. Also with all the extra stress we see with EV charging I used Noalox on all of my copper connections (absolutely no aluminum). It does two things , protects from corrosion and lubricates the connection for a better torque. For years I’ve had campers and always use Deoxit D100L on my RVs plugs, so now I’m using it on my evse plug.

 

[Jtbuster]

When I installed mine (with an electrician friend) I bought a torque screwdriver to be sure both the breaker and the receptacle had the properly rated torque levels on the screws and I was legit SHOCKED at how much torque that actually was. My Receptacle is a Cooper (Now Eaton) 5754N which is phillips head screw and couldn't take as much as the Hubbell or Byrant but at 25 inch lbs, before I got the torque screwdriver out I thought I had torqued it enough...but not even close. It took a LOT more than I thought. Thought for sure I was stripping it.

Then when we got to the breaker, for 6awg it was 40 inch lbs. That felt like a hell of a lot.

For 60 amp I'm assuming you should have used 4 awg copper and that would have needed 45 inch lbs. If you used aluminum I think that would have had to be 3 awg, 50 inch lbs.

6 awp thhp is what is spec.

 

[hprose]

I have a Ford Connected 48A charger that I run at 42 amps. Over the past three years, I've fried two 60A Eaton Cutler-Hammer style circuit breakers. This time, I'm purchasing the actual Eaton brand, as I suspect the previous ones were Eaton CH clones. I also plan to reduce the current to 36 amps. When the breaker dies the blue charger light turns off, and there’s no 240V across the terminals. Has anyone else experienced similar issues?

You need #6 wire. Nothing smaller. I noted the my 6-50 receptacle was melting one of the slots. That was causing a problem on my plugs. The receptacle was 20 years old. I replaced it with a $50 unit from Grainger that had a creamic heat sink rather than the plastic on the $10 units. Problem solved. The plug is also used for a kiln. I only unplug and plug in with the circuit breaker off.

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