First Time EV Owner - New Emporia Classic at 48A. Is this too hot?

[25StarWhiteLightning]

Just got my Ford Promise charger installed (Emporia Classic hardwired for 48A). During install they told me they planned to install 6/2 romex and I told them they can't for full rating on 60A breaker so they agreed to switch to MC cable.

I am doing a charge from 70% to 100% (road trip tomorrow) and checked on it about every 15 minutes. I noticed the cable and breaker were getting warm. At about 1 hour in I took some temperature readings. The breaker was about 122F at the surface of the breaker and the cable was about 123F where it was sitting wrapped around the charger.

Two questions:

1. Is the 60a breaker getting too hot?
2. Is the cable getting too hot?

I read the Emporia manual it doesn't specifically say the cable needs to be unwound during charging, but it might make sense (although a huge nuisance) to unwind it.

Garage ambient was probably 73F.

What is everyone else seeing?

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[bmwhitetx]

I've never measured it but I would expect it to get a little warm. Will depend on ambient of course.

I have that charger on a 60A breaker as well and I typically use the Emporia app and change amps to 40A. It's overnight and I'm not in a rush so no need to run at the limit. I will if I need to. Heat produced is I squared R, so reducing the current reduces heat by the square.

 

[25StarWhiteLightning]

Good idea on setting the power down. I was really wanting to stress test it as it was just installed. I will likely be good with derating to 40A as well.

Would love it if someone else could measure their temperatures after about an hour of full bore charging.

 

[mattbrac3]

I cannot speak to the 60A specifically, but I know when I am charging at 38A from my wall charger, the cable and breaker do get warm, but so do my other breakers for the A/C and such when they are running at full tilt in the summer. Not sure if that helps or not.

 

[JMD359]

This why it’s always best to tie it down from the max rated output your paying to heat your breaker and wiring … that would be safer and more efficient at 32 or 40 amps . Everything will last longer too. Less is more . A so think it’s all normal your running the max allowable amperage thru it for longer periods of time

 

[kf59]

I've never measured it but I would expect it to get a little warm. Will depend on ambient of course.

I have that charger on a 60A breaker as well and I typically use the Emporia app and change amps to 40A. It's overnight and I'm not in a rush so no need to run at the limit. I will if I need to. Heat produced is I squared R, so reducing the current reduces heat by the square.

You’re still well below melting point for most plastics, but generally speaking a breaker under full load should only be slightly warmer than ambient temperature. At a minimum, I would check to make sure that the wires are adequately seated into the breaker and that your electrician used the proper gauge wire. In my experience, faulty breakers off the shelf are much more common than one would expect. If smell anything, it’s time to shut it down.

 

[Newton]

This is a consequence of higher amperage continuous charging. This is the electrical equivalent of leaving an electric oven on “broil” for hours with the oven door open. Wires are going to get hot.

You definitely want to unwrap the cable if you are going to charge at that amperage. Personally I see little value in charging at higher amperage, if I had a higher amperage charger my truck would be recharged at midnight rather than 2AM. Your mileage may vary.

Your terminations are probably rated for 60C (140F)

 

[Lytning]

This why it’s always best to tie it down from the max rated output your paying to heat your breaker and wiring … that would be safer and more efficient at 32 or 40 amps . Everything will last longer too. Less is more . A so think it’s all normal your running the max allowable amperage thru it for longer periods of time

I agree. I have a 50 amp breaker and initially set the charger at 40 amps. The breaker would operate at about 125 F. I stepped down to 32 amps and the breaker now operates under 100 F. I believe in charging slowly if faster charging is not required to keep up with driving needs.

 

[bryce]

Charging my '23 Lariat on my FCSP, 80 amp breaker but have it set at 60 amp/12 kWh charge rate. The breaker temp measures 78 degrees, slightly above ambient at 65 degrees but not hot. The FCSP measures 83 degrees.

 

[Maquis]

The wIring insulation and devices are rate at 75C (167F). If it’s not too hot to touch, you’re fine.

 

[B177y]

Just got my Ford Promise charger installed (Emporia Classic hardwired for 48A). During install they told me they planned to install 6/2 romex and I told them they can't for full rating on 60A breaker so they agreed to switch to MC cable.

^^ This is the most concerning part of your post to me. The electrical contractor had to be "convinced" to use the proper wiring? This contractor was part of the Ford Power Promise deal?

As for your temperature, that's completely normal. I have a 60 amp breaker feeding a 48 amp hardwired Emporia through a short run of up-sized 3 awg in EMT conduit. The breaker gets warm, never measured but your observation seems reasonable. The Emporia cable always gets warm, again your observation seems reasonable. I have read that it is best to uncoil the cable while charging. My charger is next to my charge port so I keep my cable in a single large loop so that ther is only one layer of cable while charging to more easily dissipate the heat.

 

[25StarWhiteLightning]

^^ This is the most concerning part of your post to me. The electrical contractor had to be "convinced" to use the proper wiring? This contractor was part of the Ford Power promise deal?

Yes through QMERIT. I took the day off work to make sure they did everything right. My first question to them was what wire they were using. He had me talk on the phone with their master electrician who tried to convince me Romex is fine and they do it all the time.
They agreed to do MC cable and didn’t charge me extra but concerning. I wonder if I can tell QMERIT somehow.
It was inspected but he didn’t ask much and was there for all of 5 minutes.
Thanks for feedback on temp. I knocked the charger down to 40a and still see temperatures at that level next.

 

[25StarWhiteLightning]

The wIring insulation and devices are rate at 75C (167F). If it’s not too hot to touch, you’re fine.

I can hold my finger on it fine.

 

[RLXXI]

I have mine set to the max of 48A and leave most of the cable coiled up. Never an issue. 122°f isn't very hot at all. Your water heater is typically preset to 120°f.

Normal human temp is almost 100° (98.6°) so if you think of it in relative terms, yeah, your temp reading is fine.

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