Gen 3 cord 23 degree temp rise in 10 minutes :(

[MY-Y]

I've notice that my car shows 229 - 230 volts when charging. I decided to see where the losses are, and determined the primary issue is with the relatively thin 18' cord on the Gen 3 HPWC. The cord on my JuiceBox is much bigger. In hindsight, I wish I got the 8.5' cord or another JuiceBox.

237 volts at the breaker (4 gauge wire).
View attachment 566364

Tesla reports a 9 volt drop. Assuming both are accurate, where did most of the 9*48=432 watts go?

Here it is... Ambient temp is 102*, wire is 125*. That was just 10 minutes, I'm sure it hadn't reached steady state yet. Sigh.

 

[MY-Y]

Meant for this to be the final pic, but couldn't edit...

 

[mmanner]

For comparison, how fast did the Juicebox charge and what were the temperature differences? Are you sure that the cord temperature matters in the range you are talking about (I don't know, just asking).

 

[SilverSp33d3r]

What’s the voltage at the wall connector? And was it 237 under load or just standing voltage?

 

[MY-Y]

237 under load. There is a 36' 4 gauge copper wire in the loop, but the voltage drop from that would be very low.

 

[SilverSp33d3r]

Interesting. I would be inclined to see what kind of circuitry wire gauges are in the G3 wall connector. I have 9’ of THHN 6awg and under load(32 A) my G2 Wall connector drops 5-7 volts. I’ve attributed this to my actual utility service. It’s interesting that your FLIR is showing such a high rise in temp in the cable. Have you tried extending the entire cable to see if it changes the reads? Is the cable in the sun?

 

[ElectricIAC]

Check your breaker.

Ours was starting to get some voltage drop at 40A (243-246 standing dropping down to 227-231 under load) and wire getting hotter than usual. Had to cut charging to 26A until we could get it replaced.

 

[MY-Y]

The wire is inside my garage - no sun.

The beeaker is dropping 80 mV on one side and 120 mV on the other, so it's not the issue.

The entire 18' cable feels noticably warm when charging at 48 amps.

My JuiceBox cable doesn't get warm like this, but my van only draws 32 amps from it.

 

[kayak1]

The wire is inside my garage - no sun.

The beeaker is dropping 80 mV on one side and 120 mV on the other, so it's not the issue.

The entire 18' cable feels noticably warm when charging at 48 amps.

My JuiceBox cable doesn't get warm like this, but my van only draws 32 amps from it.

My cable also gets warm to the touch. Model Y is set for 11.5KW. My Leaf with the Juice Box only draws 6.6KW.

The Juicebox can only provide 9.6KW with a much bigger cable.

 

[MY-Y]

It's a shame to lose 4% of the overall system efficiency just because they undersized a wire.

A 9v drop at 48 amps is a .1875 ohm resistance. The wire is only 32 feet long, so this is over 5 ohms per 1000'. 16 gauge wire has a lower resistance than that, though the wires in that cable are certainty bigger than that. I'm not quite sure what is going on yet.

 

[SilverSp33d3r]

I would send your findings to Tesla. It could very well be an issue with that batch of G3 wall connectors

 

[MY-Y]

It gets a lot hotter after an hour. I hope this isn't a 60C wire!

 

[pt19713]

Charging was fine for about 90 minutes and then it drops to 24A. At least I'm still able to charge. Last week it would just shut off. This Gen3 charger makes me regret not going the NEMA 14-50 route.

 

[ElectricIAC]

Watch your voltage drop.

 

[SilverSp33d3r]

Charging was fine for about 90 minutes and then it drops to 24A. At least I'm still able to charge. Last week it would just shut off. This Gen3 charger makes me regret not going the NEMA 14-50 route.

Your voltage drops quite a bit at 48amps compared to 24.

 

[ElectricIAC]

I would consider changing your breaker. We had this exact problem and this remedied it.

 

[L_Mont]

You could try configuring the Wall Connector for 40A instead of 48A charge and see what happens.

 

[disturbed932]

Charging was fine for about 90 minutes and then it drops to 24A. At least I'm still able to charge. Last week it would just shut off. This Gen3 charger makes me regret not going the NEMA 14-50 route.

Having the exact same issue as you. Tesla pulled charging logs and determined a defective unit. I'm ok the latest firmware as well. New unit will be here tomorrow and FedEx return the current one. Exact same behavior as you. Tried everything rebooting breaker flip, etc

 

[pt19713]

Having the exact same issue as you. Tesla pulled charging logs and determined a defective unit. I'm ok the latest firmware as well. New unit will be here tomorrow and FedEx return the current one. Exact same behavior as you. Tried everything rebooting breaker flip, etc

Glad it worked out for you and Tesla is helping your situation. My car goes into the service center shortly for the due bill list, so maybe this will be a good time to talk to Tesla and get the unit back to them. Their service hours are so inconvenient (ends at 3:30 PM EST) so I'll have to find time while at work to call.

 

[Rocky_H]

You could try configuring the Wall Connector for 40A instead of 48A charge and see what happens.

Even if you don't change the configuration, you can turn it down on the car's charging screen to 45 or 42 to see how much that helps. Some of this stuff probably will be getting pretty hot running at max level, and if you don't need that benefit because you're sleeping anyway, turning it down a few amps is an easy way to help this and reduce heat.