Charging cable and adapter for NEMA 14-50 very hot

HCD3

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#1
It’s quite hot here today upper 80s. Twice the charging has stopped red light on the charge port. Any suggestions? NEMA 14-50 with a 50 amp breaker.
 
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GDN

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#2
There could always be a real issue along the way, but are you perhaps overloading the circuit or panel in a way that hasn't been before? Are you running an AC that normally isn't running or it is running longer periods of time. Seems it is protecting you by shutting down. From the screen in the car you can dial the amps down so it uses less of the load, or perhaps try charging at night when there is less load on your electrical system in the house.

Are you in an older house or have an older electrical panel with only 100 amp service or less? If so for sure dial back the amps and don't overload the panel.
 

HCD3

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#3
Thanks GDN. it’s been fine since I installed the NEMA 14-50 on a 50 amp breaker. It’s on its own circuit, nothing else on it. Wondering if my UMC has gone bad. Fairly new house with 200 amp service.
 

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#4
It’s quite hot here today upper 80s. Twice the charging has stopped red light on the charge port. Any suggestions? NEMA 14-50 with a 50 amp breaker.
Is the charging unit in the sun?

I had the same problem with two different EVSE's when it was really hot outside, charging at a higher current and when the EVSE was in the sun. When I moved the EVSE to the shade, the problem went away. Also, you could try lowering the current a little bit just to see if that helps.
 

HCD3

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#5
Thanks. NEMA 14-50 is in the garage. I’ve been charging at 32 amps, the max that my inboard charger can do. I’ll try lowering the amps a bit next charge. Interestingly today I was only charging at 28 amps. I usually am able to charge at 32 amps, 30 mph. I checked twice to make sure the UMC was seated in the charge port.
 

FF35

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#6
Do you know anyone that has the same UMC? If so, I would ask to try it to see if the problem still exists.
 

HCD3

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#9
Is there anything getting hot?
The wall receptacle or adapter?
The UMC (box in the cord)?
The cord?
The wand?
The charge port in the car?
The cord, the wand, and the Tesla block connector. Even unplugged the block is warm. No current going to my car.
 

Feathermerchant

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#10
Mine is warm when plugged in to the wall but not the car. I think that is normal.
It is NOT normal for it to stop the charge. Did it show a fault on the screen in the car?
Do you have an IR temp gun?
If all the pieces feel about the same temp and you can hold on to them then the temp is probably OK.
You can always turn the Amps down to 25 or so.
Trying the other one is also a great idea.
 

jdcollins5

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#11
I would check the connections at the 14-50 receptacle and at the breaker. I installed my 14-50 receptacle and know the connections were tight. I checked again about a month later, after numerous thermal cycles, and could tighten all connections another 1/4 turn.

Mine is just slightly warm while charging.
 

JasonF

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#12
In order of likelihood:

First, pull the adapter head off of the Mobile Connector and then re-seat it. While you're removing it, examine the connections and make sure none of them have melted (then you'll need a replacement head). If it all looks ok, make sure it's seated so it's flush with the top of the Mobile Connector.

If that doesn't solve the issue, turn off the 50 amp breaker and pull the outlet out of the wall. Make sure none of the wires have loosened from heat, and tighten up any screws as necessary. If the outlet appears damaged or melted, replace it. If the wiring to the outlet is melted or blackened, it might not be large enough to handle 32 amps (that's rare for professional installs, but you never know).

If those fail, check the circuit breaker and make sure its pushed down completely into the bus bar, and the wire screws are tight, as well as the connection to ground. Use an electrician for this part if you don't feel comfortable with messing around in the circuit box.

If all of those fail to fix the problem, then you most likely have either a bad Mobile Connector, adapter head, or charge port - and usually failures occur in that order.

Don't worry about air conditioners or overloading the entire house. If you're able to run your air conditioning and your dryer or stove at the same time, your electrical system should be able to handle charging a car (it uses close to the same number of watts as a dryer or a stove). Household 200 amp service should be enough.

FYI to those who might have an older panel with 100 amp household service, Tesla does have a feature to deal with that - you can set charging to begin at a time when it's cooler out so A/C isn't running as much, plus you won't be cooking food or doing laundry.
 

JWardell

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#13
It's hard to judge what too hot means, so I will instead say: can you smell burning plastic?
The most common issue is that the cables feeding the 14-50 outlet were not installed tightly enough, and over time loosen then scorch and then really melt things. Take a sniff around the outlet.
It is normal for everything to be warm to the touch, but should not be too hot to handle.
The car also knows where the over temperature is (the plug, the adapter, the cable, etc)...not sure if the message on screen hints to that.
If current is reduced a bit then also check the cleanliness of all contacts.
 

mswlogo

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#14
What brand 14-50 socket? Leviton’s are known to have wimpy contact. Lot of folks recommend Hubble.
 

HCD3

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#15
In order of likelihood:

First, pull the adapter head off of the Mobile Connector and then re-seat it. While you're removing it, examine the connections and make sure none of them have melted (then you'll need a replacement head). If it all looks ok, make sure it's seated so it's flush with the top of the Mobile Connector.

If that doesn't solve the issue, turn off the 50 amp breaker and pull the outlet out of the wall. Make sure none of the wires have loosened from heat, and tighten up any screws as necessary. If the outlet appears damaged or melted, replace it. If the wiring to the outlet is melted or blackened, it might not be large enough to handle 32 amps (that's rare for professional installs, but you never know).

If those fail, check the circuit breaker and make sure its pushed down completely into the bus bar, and the wire screws are tight, as well as the connection to ground. Use an electrician for this part if you don't feel comfortable with messing around in the circuit box.

If all of those fail to fix the problem, then you most likely have either a bad Mobile Connector, adapter head, or charge port - and usually failures occur in that order.

Don't worry about air conditioners or overloading the entire house. If you're able to run your air conditioning and your dryer or stove at the same time, your electrical system should be able to handle charging a car (it uses close to the same number of watts as a dryer or a stove). Household 200 amp service should be enough.

FYI to those who might have an older panel with 100 amp household service, Tesla does have a feature to deal with that - you can set charging to begin at a time when it's cooler out so A/C isn't running as much, plus you won't be cooking food or doing laundry.
Thanks Jason I reseated the adapter and I’m charging as we speak it seems OK. I do know the ambient temperature in the garage was nearly 100 degrees. This morning the block with the cascading green Tesla leds was normally warm. Last night it was very hot. I’m going to schedule charging until it cools off here.
 

HCD3

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#17
It's hard to judge what too hot means, so I will instead say: can you smell burning plastic?
The most common issue is that the cables feeding the 14-50 outlet were not installed tightly enough, and over time loosen then scorch and then really melt things. Take a sniff around the outlet.
It is normal for everything to be warm to the touch, but should not be too hot to handle.
The car also knows where the over temperature is (the plug, the adapter, the cable, etc)...not sure if the message on screen hints to that.
If current is reduced a bit then also check the cleanliness of all contacts.
Thanks Josh. As I mentioned, the temperature in the garage was around 100 degrees. This morning I completed yesterday’s partial interrupted charging session, and everything was cool to the touch. Much cooler here. It charged at 28 mph and 32 amps as normal. No burning plastic smells. I reseated the 14-50 adapter into the block and unplugged an plugged the plug back into the receptacle. It worked fine. My electrician is coming this afternoon to check all the connections. I looked at the connector that goes into the charging port and it’s fine. I’ll let you know his diagnosis.
 
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JasonF

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#18
Thanks Jason I reseated the adapter and I’m charging as we speak it seems OK. I do know the ambient temperature in the garage was nearly 100 degrees. This morning the block with the cascading green Tesla leds was normally warm. Last night it was very hot. I’m going to schedule charging until it cools off here.
I've been charging in a 100 degree garage from July to October last year, and this year since May (I'm in FL) and it doesn't cause any problems. I'm in the process of insulating the garage doors (it's hotter close to them because of the evening sun beating on them) both because a 100 deg garage is miserable to do stuff in, and because it can't be all that great for the battery cooling system. If I can lower it just a few degrees it will be better overall.