Struggling with overheating…

[RidingwithScotty]

Hi!

So I’ve run into a bit of a frustrating conundrum with Scotty. One of the reasons I felt comfortable getting him was the house my family lives in coming with a 14-50 outlet in the garage built in during new construction. However, I’m now wondering how great of a perk that was…

After encountering hot plugs while charging and overheating with the FMC, I’ve swapped it out for a classic Grizz EVSE and swapped out the builder grade outlet for a Bryant 14-50 from Grainger. Still had a hot plug while charging occasionally; changed the settings on the Grizz to 32 amps max out of an abundance of caution and have still run into a warmer than desired plug. Now this last time my dad had been charging his Tesla at the 32 amp max to allow me to charge later that evening, but should it still have been warm while charging Scotty after sitting for 40 minutes? Of course I get to hear a little bit of Tesla elitism with that app allowing you to adjust the amps whereas Ford doesn’t; I love how my my baby drives and looks so that’s that. But I am wondering what could be causing this aside from the scary Occam‘s razor answer of wiring not being adequate for the task at hand…

Any suggestions/advice would be gratefully welcomed.

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[BTRYPWRDPONY]

What gauge wire are you running to the outlet?

 

[kodiakng]

What gauge wire are you running to the outlet?

and how far is it away from the panel?

 

[macchiaz-o]

You can adjust the max amperage at your Grizzl-E. Reduce it down if a lower setting satisfies your daily needs.

How warm is warm? Does the area receive direct sunlight?

 

[kodiakng]

to add a bit to the terse comment above:

the Bryant 9450FR Industrial receptacle is a good one so if that is what you swapped in it should be ok. you don't mention who swapped out the receptacle but torquing the connections appropriately is important too.

the next place to check is the wire from the panel to the receptacle. the most important check is the gauge of the wire as @BTRYPWRDPONY asks. you want at least #6 wire as that should work well for up to 150 ft runs to the panel. if you're further than that you'll want #4.

in the meantime, if the heat on the plug is uncomfortable to put your hand on, even with the Grizz EVSE set to 32A, you might drop it even more (24A appears to be an option) to be safe until you can have the wiring checked out.

[minor edit]

 

[RidingwithScotty]

Wow, y’all are quick to respond! I will have to check the gauge on the wire at some point this week.

The outlet is at the back of the garage so it doesn’t receive direct sunlight unless the garage door is left open for hours at a time. It isn’t far from the breaker panel (I will try to get a picture for reference).

Heres the outlet I swapped it out with: https://www.grainger.com/product/GRAINGER-APPROVED-Receptacle-Single-49YY93. Blessed to have a handy dad who torqued the connections (since he has a Tesla which also uses this setup, has done handy work for decades).

The plug has been uncomfortable to touch for long periods of time, and we’ve greased the new plug with Dielectric grease to ensure proper contact. If need be, I don’t mind changing the max current again but I do wonder if I should have to do it if the wire is the proper gauge.

 

[Maquis]

Wow, y’all are quick to respond! I will have to check the gauge on the wire at some point this week.

The outlet is at the back of the garage so it doesn’t receive direct sunlight unless the garage door is left open for hours at a time. It isn’t far from the breaker panel (I will try to get a picture for reference).

Heres the outlet I swapped it out with: https://www.grainger.com/product/GRAINGER-APPROVED-Receptacle-Single-49YY93. Blessed to have a handy dad who torqued the connections (since he has a Tesla which also uses this setup, has done handy work for decades).

The plug has been uncomfortable to touch for long periods of time, and we’ve greased the new plug with Dielectric grease to ensure proper contact. If need be, I don’t mind changing the max current again but I do wonder if I should have to do it if the wire is the proper gauge.

According to the description in the link, the receptacle has “screws that tighten on the wire.” That’s a sign of an inferior design that has been prone to failure. The high-quality ones have saddles that clamp on the wire - the screws themselves (with the associated twisting action) don’t touch the wire.

 

[RidingwithScotty]

Here‘s a photo of the outlet/ breaker. Doesn’t look to be too far away but I could be wrong.

 

[kodiakng]

The outlet is at the back of the garage so it doesn’t receive direct sunlight unless the garage door is left open for hours at a time. It isn’t far from the breaker panel (I will try to get a picture for reference).

if the distance is less than the length of your garage you should be fine.

Heres the outlet I swapped it out with: https://www.grainger.com/product/GRAINGER-APPROVED-Receptacle-Single-49YY93. Blessed to have a handy dad who torqued the connections (since he has a Tesla which also uses this setup, has done handy work for decades).

that's the good one.

The plug has been uncomfortable to touch for long periods of time, and we’ve greased the new plug with Dielectric grease to ensure proper contact. If need be, I don’t mind changing the max current again but I do wonder if I should have to do it if the wire is the proper gauge.

changing the max current on your EVSE is just a bandaid until the root cause of the heat is found. i should also have mentioned the wire should be copper and not aluminum. i don't think you find aluminum in new construction now days but best to be sure.

if the wire is #6 and copper you might need to look at the plug on the Grizz EVSE.

 

[kodiakng]

According to the description in the link, the receptacle has “screws that tighten on the wire.” That’s a sign of an inferior design that has been prone to failure. The high-quality ones have saddles that clamp on the wire - the screws themselves (with the associated twisting action) don’t touch the wire.

this amazon link to the same model notes a lug type terminal with captive allen head terminal screws. does that sound better?

EDIT: a better amazon link with actual pics of the back side. @RidingwithScotty do this model match up with what you have?

 

[21st Century Pony]

...and the best solution to avoid weak, overheating connection points is to hard-wire the EVSE.

We have two Grizzl-E EVSEs - I have the basic one and Sonny Boy, two states over, has the Grizzl-E Duo, for when I visit. We hard-wired both Grizzl-Es in. This avoids the plug failure point.

Please do check the wire gauge. This is a "thicker = better" situation since the thicker the wire (thicker = lower gauge #), the lower the resistance in the wire under an electrical load, and less resistance = less heat buildup.

Good luck!

 

[AKgrampy]

We can provide all the advice in the world but the simple fact is if things are getting warm to the touch something is wrong and you should hire a professional to figure it out.

 

[Mrn]

I expect a receptacle drawing 40 amps at 240 volts (9.7 KW) to be quite warm but not hot to the touch. If your dad torqued the clamps only once, someone with good knowledge of home electrical installation should turn off power to the outlet and do a second torquing. They can loosen after a few days of settling in.

 

[BTRYPWRDPONY]

to add a bit to the terse comment above:

the Bryant 9450FR Industrial receptacle is a good one so if that is what you swapped in it should be ok. you don't mention who swapped out the receptacle but torquing the connections appropriately is important too.

the next place to check is the wire from the panel to the receptacle. the most important check is the gauge of the wire as @BTRYPWRDPONY asks. you want at least #6 wire as that should work well for up to 150 ft runs to the panel. if you're further than that you'll want #4.

in the meantime, if the heat on the plug is uncomfortable to put your hand on, even with the Grizz EVSE set to 32A, you might drop it even more (24A appears to be an option) to be safe until you can have the wiring checked out.

[minor edit]

What dis guy says

 

[Say Watt]

How warm is too warm? There will be some heat around any "temporary" connection. Get some actual numbers with a digital thermometer. (This is a great tool even for checking your HVAC vents in your house.) If your wiring is sound, the problem could be on the Grizzl-E side.

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