Wall connector temperature readings in Wall Monitor App

[en9ine]

Curious what everyone’s temperature readings are according to the Wall Monitor app.

While not charging, my gen 3 Tesla wall connector (revision G) consistently reads at the MCU about 18 degrees Fahrenheit above ambient. For example currently it’s 52F outside, but MCU reads 70.5F and PCBA 59.4F. Screenshots attached.

Slightly concerned about the 70.5F reading given it’s only 52F outside, but if consistent with everyone else’s readings then doesn’t seem like a big deal.

On the latest firmware 23.8.2, but it’s been like this since I can remember except when first installed last month.

Thanks.

 

[Sophias_dad]

I wouldn't be concerned. The MCU is probably still awake for whatever reason and that means it'll be generating heat. I'd also think that even after its gone back to sleep it would still be warm for quite some time. Maybe check it in the morning or after a few hours asleep(which can be hard to predict since it'll start charging again at intervals on its own).

I'm surprised the relays read 11.9 volts while not charging(but I haven't checked my own yet). I saw they hover at ~6V when charging but I assumed that was because they jumped to ~12V to engage and then reduced to 6V to hold-in.

 

[fiehlsport]

Mine is always a bit warmer than ambient - it's a chip with current running through it, to be expected. My MCU temp is 77F right now in a ~61F garage.

I'm more curious about your 215V line voltage while not charging... Do you have 240V at the mains??

 

[en9ine]

Ah interesting. Thanks for checking. That datapoint about your MCU being about 16F above ambient helps put me at ease a bit.

So yeah—regarding the 215 line voltage while not charging. I don’t really know much about it but maybe someone can explain.

Btw, I’m in NYC and apparently phase and voltage here is a little … special?

 

[Art84]

215V is kind of all right... Normal range is between 220-240, but 215 is close to that range
Probably the main line experience a high load in your area which may drop the voltage. Don't be concerned about it at all..

 

[dafish]

215V? That’s well below any reasonable voltage.

240 is nominal single phase 2 leg voltage at the pole/transformer. Home equipment is expected to see 230. (I’ll see if I can find references on this). Here in Illinois the utility must deliver within 7v at 120, or 14v at 240, so 226V,or the ICC fines them.

So no, not normal.

 

[Sophias_dad]

Ah interesting. Thanks for checking. That datapoint about your MCU being about 16F above ambient helps put me at ease a bit.

So yeah—regarding the 215 line voltage while not charging. I don’t really know much about it but maybe someone can explain.

Btw, I’m in NYC and apparently phase and voltage here is a little … special?

215 is quite low. The car/charger won't care, but other equipment in you home might.

https://www.pge.com/includes/docs/p...ergystatus/powerquality/voltage_tolerance.pdf suggests that if you have ongoing voltage below 216 volts the utility should be correcting it. Note that that's the delivered voltage(to your panel) not the voltage after some losses between your panel and your HPWC(in reality in your case there will be no losses since you aren't actively charging during your screenshots).

I had a friendly chat with my electric provider due to low voltage and they came and replaced a transformer. It didn't get me regularly above 240V, but at least its regularly 230 or better.

I have some suspicion that low voltage is what killed off my AC compressor early.

 

[dafish]

 

[dafish]

A reference on voltages and what they are supposed to be and where

Voltage Ratings: 110/115/120, 220/230/240 or 440/460/480

This subject comes up a LOT in this and other forums, so I thought it would be a good idea to make it a "Sticky" that can be found and referred to easily when it comes up. There are two "standards" for voltage in North America depending on which END of the wire you are looking at; "Distribution...

forums.mikeholt.com

 

[Art84]

215 - it's quite low, but there are no issues with that.
Everything that you plug in - will work just fine. You will not damage any of your equipment. You just get little less power in KWh.

 

[en9ine]

Thanks for all the replies. I just want to point out that when I said that NYC is "special," I mean that I have only read that NYC delivers 208V in various parts of the city and 240V to other parts—all anecdotal because this is information I've read in unverified forums, and I'm not an electrician or anything even close. I know from the Wall Monitor app that when the car is actually charging, the voltage hovers around 207-208.

I haven't actually taken a voltage meter to the main nor do I know whether my home gets single or 3 phase service. My home isn't really that complicated or modern, and quite modest... built in the 1920's with 100amp service with no central AC system and a simple heating furnace w/ cast iron radiators.

 

[Rocky_H]

There are the two nominal voltage levels you would find in various buildings throughout the U.S. They are either 208V or 240V, and it's usually easy to tell which it is, because it will be obviously closer to one or the other. 215V is so in the middle, it's hard to tell if it's a high 208V supply or a low 240V supply.

 

[dafish]

215V off a 208V three phase is pretty likely. Not good for 240 motors/compressors in my opinion, and I believe generally voids warranty's of same.

 

[ttom3]

How about temperature while charging shown by the Wall Monitor App? This is today, almost 136F at the circuit board on a 60F garage temperature while pulling just short of 40A to a Model 3. The Tesla wall connector is a J1772 Gen 3 on a 60A circuit breaker.

 

[ttom3]

Also interesting to me is the unequal A and B current and bouncing N current from 0 to 39.6A. I have a 2022 Ford Lightning and it shows the same as our son's Model 3 charging. Got the Tesla J1772 wall connector as I liked the idea of possibly getting a second one and having them communicate to each other.

 

[Sophias_dad]

I don't think the N current reading is valid. There's no N connection on the HPWC.

Regarding the temperature, 139F isn't really THAT unexpected, surprisingly enough. Those poor relays are trying to move 24 amps per contact(20 in your case), and it doesn't take many millohms before there's significant power dissipation(I^2 times R, and all that), and if the two contacts(per relay) aren't evenly matched, the one with lower resistance will end up taking more of the current(I^2 can be a pretty harsh factor)

Before Tewamo, just reading the relay case temperature, it was north of something like 200F before throttling occurred. See Gen3 HPWC disassembly, with overheating issues explained! for the gory details.

I wonder if some of the j1772 HPWCs have defective relays.

 

[ttom3]

Part number on J1772 Tesla wall connector (manual says Gen 3) is: 1509549-02-B for $550 October, 2022. Got $400 back in a rebate.
Wonderful work you did on ripping apart the wall connector relay and testing stuff. You could start a GoFundMe to buy stuff for testing questionable products. A real Consumer Reports!
And Thanks for the Tesla Wall Connector monitoring, free Tewamo App for Android, reference. Only seems to calculate cost in Euros?

 

[Sophias_dad]

And Thanks for the Tesla Wall Connector monitoring, free Tewamo App for Android, reference. Only seems to calculate cost in Euros?

Under 'settings' (The gear icon) in Tewamo you can set 'currency' to '$'

 

[ttom3]

With the TPN 1509549-02-B J1772 wall connector in a warm garage, 78F outside, maybe 95F inside, running at 40A for 2 hours, the Android Tewamo App is showing PCB at 153.5F, MCU at 135.86F; the Handle outside at 120F in sun. The A/B Amp imbalance is 18.4/21.1 = 39.5 Amps. I should try 32 and 48Amps settings (on my 60A CB) to see temperature differences. Anyone else reporting temperatures this high? 60A CB infrared reading about 106F at this 40A flow.
Here is someone reporting failures and found the PCB was reaching 203F! Wall Connector charging decreases amperage over a long charge

 

[JWM3]

My outdoor charger is displaying temperatures of 199.2°F for the PCB and 103.5°F for the handle while it's in use. This is happening on a cloudy day with an external temperature of only 65°F.
Is this within the expected range? I'm beginning to have concerns about the durability and performance of my wall charger.