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With 2 different EVSE's, the plastic face of my Leviton 14-50R has been measuring 156F with an IR thermometer when charging at 32 amps. So I checked for loose connections and found none. Then I replaced the Leviton with a Pass & Seymour Legrand, and the face of the receptacle read 175F!

So I pulled out the metal box and all the wires back to the breaker. The plastic bushings on the box and service panel looked fine. The neutral wire looks great, but you can see some distortion of the outer clear jacket of the hot wires as shown below. There are no nicks of the red and black jackets, and no tarnish of the copper. I did notice that the ground pigtail was loose in the wire nut, but that couldn't have caused overheating, right? What's my next diagnostic step?
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With 2 different EVSE's, the plastic face of my Leviton 14-50R has been measuring 156F with an IR thermometer when charging at 32 amps. ....
replaced the Leviton with a Pass & Seymour Legrand, and the face of the receptacle read 175F!
... I did notice that the ground pigtail was loose in the wire nut, but that couldn't have caused overheating, right? What's my next diagnostic step? View attachment 45005
Good job of testing things and troubleshooting the obvious!
The ground should not be the problem as all the current flow is between the two phases of the hot wires. The ground does not flow anything.

Is the EVSE connector the source of the heating, possibly? It could have bad pin to wire crimps.
Next time you have it charging for a while, unplug and measure both sides of this connection, the pin and socket sides.

Is the wire gauge correct? While you have it out you could go one thicker....

Keep us up to date!
 

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With 2 different EVSE's, the plastic face of my Leviton 14-50R has been measuring 156F with an IR thermometer when charging at 32 amps. So I checked for loose connections and found none. Then I replaced the Leviton with a Pass & Seymour Legrand, and the face of the receptacle read 175F!

So I pulled out the metal box and all the wires back to the breaker. The plastic bushings on the box and service panel looked fine. The neutral wire looks great, but you can see some distortion of the outer clear jacket of the hot wires as shown below. There are no nicks of the red and black jackets, and no tarnish of the copper. I did notice that the ground pigtail was loose in the wire nut, but that couldn't have caused overheating, right? What's my next diagnostic step? View attachment 45005 View attachment 45006
The black and red hot wires are the only thing with any current on them with a properly functioning EVSE. A 14-50 should have 6 AWG copper fed into it to be up to spec. 8 AWG could be used in a situation where you're on a 40A circuit, but I personally would not do that. I can't tell the wiring size here, but 156F would technically be in spec if these are THHN wires. NM-B should not be allowed to get hotter than 140 F
 

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The black and red hot wires are the only thing with any current on them with a properly functioning EVSE. A 14-50 should have 6 AWG copper fed into it to be up to spec. 8 AWG could be used in a situation where you're on a 40A circuit, but I personally would not do that. I can't tell the wiring size here, but 156F would technically be in spec if these are THHN wires. NM-B should not be allowed to get hotter than 140 F
Up-size absolutely everything unless you're an electric engineer or electrician is my gospel to everyone.
 

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I assumed since 2 different EVSE's are overheating that the pin to wire crimps could not be the cause. Was that not justified?

Everyone, the wire gauge is 6.
I didn't mean to dodge your issue but I also didn't want to be hypocritical as a non-electrician/engineer.

For me, if something is hot, it's the hot thing where the resistance is likely no good. I'd have started with replacing the hot thing first.
 

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I assumed since 2 different EVSE's are overheating that the pin to wire crimps could not be the cause. Was that not justified?

Everyone, the wire gauge is 6.
If two different EVSEs overheated when plugged into you 14-50 receptacle, I would replace the receptacle.
 

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14-50 outlets vary in quality/durability. This video compares 5 different brands of 14-50 outlets. I purchased a cheap Leviton unit from a big box store. Then I did some research and found the one Tesla recommends (Hubbell) is the preferred outlet mentioned in this video. I returned my Leviton and purchased the Hubbell.

Unfortunately the Hubbell has more than doubled in price since this video was made 2 years ago. It was $68 in the video. I paid $80 for mine about a year ago. Now it's on Amazon for $100+. Check the reviews on Amazon for pictures and more info.

If you get the Hubbell outlet, you will need a specific face plate for it as a standard 14-50 plate won't fit (it's too small).
 

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I assumed since 2 different EVSE's are overheating that the pin to wire crimps could not be the cause. Was that not justified?

Everyone, the wire gauge is 6.
So two different EVSE's and two different brands of 14-50 outlets.
How long is the 6 ga. wire run?

You sir, have a mystery. But it is solvable.
Any chance both EVSE have bad plugs and those are the source of the heat? (WAG....)
 

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This isn't limited to 240, I've plugged L1 charger into brand new outlets and was extremely uncomfortable with the heat being generated at the contact point while on vacation.
 

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14-50 outlets vary in quality/durability. This video compares 5 different brands of 14-50 outlets. I purchased a cheap Leviton unit from a big box store. Then I did some research and found the one Tesla recommends (Hubbell) is the preferred outlet mentioned in this video. I returned my Leviton and purchased the Hubbell.

Unfortunately the Hubbell has more than doubled in price since this video was made 2 years ago. It was $68 in the video. I paid $80 for mine about a year ago. Now it's on Amazon for $100+. Check the reviews on Amazon for pictures and more info.

If you get the Hubbell outlet, you will need a specific face plate for it as a standard 14-50 plate won't fit (it's too small).
I've just bookmarked this video for future referencing for when this comes up. Very helpful for newbs like me who don't know the first thing about the quality of outlets.
 

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Sad. Our 14-50 receptacle, which I installed five years ago, is a Leviton. I went back in and retightened the set screws, after the first few charges. I often feel the 14-50 plug and receptacle, J1772 plug and receptacle, and breaker, while the Bolt is pulling 7.6 kW. Everything always feels about body temperature.

Here is a shot showing charge port temperature, after charging to hilltop, in June.

Product Font Technology Rectangle Screenshot


Back when we first had the Bolt, I got a Juicebox 40 Pro. It had a bad wire crimp in the molded plug. It got hot. They replaced it, and the next one had a component fail in the electronics. I returned it, and we have had a Tesla Gen II ever since.
 

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Discussion Starter · #18 ·

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Sad. Our 14-50 receptacle, which I installed five years ago, is a Leviton. I went back in and retightened the set screws, after the first few charges. I often feel the 14-50 plug and receptacle, J1772 plug and receptacle, and breaker, while the Bolt is pulling 7.6 kW. Everything always feels about body temperature.

Here is a shot showing charge port temperature, after charging to hilltop, in June.

View attachment 45018

Back when we first had the Bolt, I got a Juicebox 40 Pro. It had a bad wire crimp in the molded plug. It got hot. They replaced it, and the next one had a component fail in the electronics. I returned it, and we have had a Tesla Gen II ever since.
I'm not too impressed with Juicebox even though I'm about to get a second one installed. Stupid utility requirements for discounts and rebates. The J1772 feels cheap in comparison to its price point and I'm not surprised you had a problem with your plug. You're not even supposed to install it in a place that receives direct sunlight. All for one of the most expensive units out there. I'm hoping it's easy enough to set a max of 60 amps out of both units without too much fussing on the fly. I only have 100 amps going to the house and am going to be relying on Juicebox to distribute.

There are some things Tesla just didn't leave to question, charging and electrical components appears to be one of those things.
 

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In addition to Hubbell, I've read that Bryant 9450fr and Cooper 5754n are good.

What you see in the photos.

No, but that might be interesting. Both of my EVSE's measure the current.
My GM OEM EVSE that came with the EUV pulls a little less than 32 amps on each hot. I have it hooked up to an external Chicago Electric 14-50R on a 40amp circuit breaker that does get warm to the touch, but the 8 ga romex wiring is just slightly warm. No high temp sensed at the outlet either. Seems normal to me.
 
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