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Is it normal for the wall connector cable to get hot @80 amps?

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Mostly the box in the middle and the plug got hot on the UMC. I monitored the voltage displayed as the current ramped from 0 to 32 and it went from 240 to around 234. I don't think he reset the outlet under load.
Sounds like the source of your heat is in the outlet/plug, and the heat got conducted down the wire to the control box. My guess is a loose connection in the outlet, or less likely, the UMC wasn't plugged in all the way, so there was sketchy contact at the outlet/plug interface.

You have 6V*32A=192W being dissipated somewhere. Over a long wire run, that's not much heating (when charging I lose ~5 volts in the utility's overhead wires before coming into the main bus bars), but if the bulk of it was concentrated at the outlet connection, it would get pretty hot.
 
I have 2 HPWC's. Each at 80A charge setting. I noticed my wife's model X was reducing the charge rate to 60A from 72. I checked the cable it's clean and clear.
I charged my Model S on it to see if maybe it was the Model X charge port, as my Model S does not get too hot on my other HPWC at 80A.
I measured the handle temp and it got to 160F! Today a ranger came out and he said "he's never seen one get that hot" (I left the car charging for couple hours at his arrival)
He's saying that it's a good idea to change the charge cable. (duh!)
My question is, will this actually resolve the issue? I'm not trying to burn down my house.
 
I have 2 HPWC's. Each at 80A charge setting. I noticed my wife's model X was reducing the charge rate to 60A from 72. I checked the cable it's clean and clear.
I charged my Model S on it to see if maybe it was the Model X charge port, as my Model S does not get too hot on my other HPWC at 80A.
I measured the handle temp and it got to 160F! Today a ranger came out and he said "he's never seen one get that hot" (I left the car charging for couple hours at his arrival)
He's saying that it's a good idea to change the charge cable. (duh!)
My question is, will this actually resolve the issue? I'm not trying to burn down my house.

That should resolve the issue. Probably a loose connection. Keep in mind that those components are designed for heat stress. 160F isn't good but those plastics can withstand >200F without significant deformation and even higher before theres any risk of a fire. Your car would fault out and stop charging long before that happens. No Current. No Heat. No Fire.

Heat will cause components to degrade and loosen more rapidly. Getting loose causes more resistance => more heat => faster degradation. This is why I only charge >20A when I need it. Why charge @80A and charge in ~2 hours when I don't have plans for ~12?
 
Heat will cause components to degrade and loosen more rapidly. Getting loose causes more resistance => more heat => faster degradation. This is why I only charge >20A when I need it. Why charge @80A and charge in ~2 hours when I don't have plans for ~12?
People frequently ask about whether they should turn down their home charging to be less stressful on the battery. I always redirect them that they are looking in entirely the wrong place. The battery will be fine, but your explanation is spot-on about why it does make some sense to use lower current for daily use if you don't want to stress the components in your charging equipment.
 
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It does get somewhat hot. As for how hot is OK, you may want to check with your Tesla local service people. It's never bothered me.

Also, remember that your battery can handle 80A and supercharging, but it'll live longer and age more gracefully if you charge more slowly. Also, lithium-ion batteries are happiest (and age best) when they spend as little time as possible either full or empty. If you use 50% of the battery on a day with lots of driving, for example, you may want to charge only to 80% so your use of the battery ranges from 30% when you come home to 80% the next morning.

Since I rarely needed more than 100 miles in a day, for example, I charged my Model S to 75%, giving me rated range of 195 miles. I'd come back home with 75-100 miles of rated range left in the very worst days (about 30% to 40%), and I've charge overnight at 20A/240V so it would take 5-6 hours to recharge back to 195. Lastly, every month or two, I'd do a full charge to 100% so the pack would "balance" itself.

I was never ever stressed for lack of range, and after four years my battery still held 98% of its original range. Anecdotal yes, but based on good science. Make sure you aren't living with range anxiety, there's no need for that. But while keeping enough range so you always have a great reserve, charging to a lower maximum will keep your battery healthier over time. You don't have to do any of this, but you have the choice if you want to baby your car and keep it in the best possible shape.
Does it not increase the number of charge cycles by shortening the drive/charge window thereby reducing battery life by means of that?
 
Charge cycles are based on the amount of energy exiting and entering the battery, not the speed of the charge. Whether you charge from 85-90% 20x or 0-100% one time, the battery is subject to the same single charge cycle.

I always charge to 90% for daily use and 100% when leaving for a trip where I need the extra range, or I anticipate needing to supercharge. A battery at a lower SoC also produces less power, and that's less fun.
 
Here's the temperature of our original gen 1 HPWC plug charging at 80A when it was originally installed on a 100Q circuit by Testla's recommended licensed electrician. Tesla Ranger came out and verified this was WAYt too hot... and replaced our HPWC cable with a new one which dropped the temperature dramatically (less than 1/2).

IMG_3344.jpeg
 
The pink area is where the temperature was the hottest when charging. New cable kept charging temps MUCH lower for 6 more years... until our gen 1 HPWC decided to fail completely (no power light) so I replaced it with a brand new gen 2 Wall Connector.

I lowered my nightly charge rate to 60A after seeing how hot the Wall Connector cable got at 80A. It gets warm but never hot so should last another 6+ years.

IMG_3338.jpeg
 
I still have my "dead" 6-year old gen 1 HPWC with a perfectly working cable. Would love to sell it for parts to someone who can troubleshoot and repair it... or harvest the charge cable. Prefer local pickup at our home in Newport Coast, CA 92657 since boxing it up and shipping is a PITA.
 

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I still have my "dead" 6-year old gen 1 HPWC with a perfectly working cable. Would love to sell it for parts to someone who can troubleshoot and repair it... or harvest the charge cable. Prefer local pickup at our home in Newport Coast, CA 92657 since boxing it up and shipping is a PITA.
If you're willing to ship, I'm definitely interested.
 
Does it not increase the number of charge cycles by shortening the drive/charge window thereby reducing battery life by means of that?
Actually it's much better to perform a lot of small charging sessions than one large session, given the same number of miles traveled. @nwdiver summed it up nicely in his post.
But 85 - 90% 20x causes significantly less wear on the battery than 0-100% once.
One of the factors that contributes to cell breakdown is the volume of expansion and contraction of the Li particles. These particles develop microcracks that ultimately shorten the life of the cell. Large swings in state of charge means larger physical expansion and contraction which leads to more microcracks. Small changes in SOC cause almost no microcracking. That's why 20 charges of 5% has much less impact than one cycle of 100% even though it's the same amount of total energy. That's why Tesla recommends plugging in every day no matter how far you drive.
 
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Note that I was not referring to wear. I was clarifying the defintion of a "charge cycle" which is one charge from 0-100, or 100 charges of 1% each.

Increasing the frequency or reducing the amount of energy per charge does not change the number of charge cycles. The car actually keeps track of these and you can read them by using a scanner app.
 
If you're willing to ship, I'm definitely interested.
I still have my "dead" 6-year old gen 1 HPWC with a perfectly working cable. Would love to sell it for parts to someone who can troubleshoot and repair it... or harvest the charge cable. Prefer local pickup at our home in Newport Coast, CA 92657 since boxing it up and shipping is a PITA.
SOLD to TMC member tga for $100 + shipping to New Hampshire
 
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