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Wall Charger issue

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I just got my first Tesla two weeks ago (M3P). I finally received my wall charger 5 days ago (Gen3). The owner of the company i work for gave me permission to install the wall charger at work. I had it installed by our in house electrician. It powers up perfectly. It took me a couple days to get wifi to it to complete the firmware/software updates. That's all done now. I plugged in to my M3, Ive got the green flowing lights on the charger, green flashing light on the charge port. The screen in the car says its charging, However, all the charge stats at the bottom of the screen say zero.
I feel pretty confident the all the setting are correct. In doing some online research, i keep seeing that the north American cars and chargers are only designed for single phase. I work at a manufacturing facility that only has 3 phase, which is where ive installed this charger.
So, am i on the right track here as far as what the issue is?
Why didn't the charger or the car detect this issue immediately?
And most importantly, does anyone know a workaround for this?
And yes, Ive tried contacting tesla support..... They went out for a pack of cigarettes the moment i signed the purchase agreement...
 
OK. For those that haven't seen this before, I'm just a-doing the math. Hang in there.

Take standard house wiring. There's three wires that cometh down from the power pole. Take the easy one first: One wire is Neutral; it goes to the breaker box in the house and, incidentally, gets connected to a thick, 6' or so long copper stake that was pounded into the ground when the house was built. (Yes, that's where all the green "ground" wires in a house are connected to.) At the breaker box, neutral and ground are one and the same thing. Everywhere else, not so much.

Next, those other two wires. Each one of those wires is a Hot. Imagine a sine wave. Starts at zero, ramps up to 170V or so, then ramps back down to zero, then ramps down to -170V, then ramps back up to zero volts again, lather, rinse, repeat. That's one hot.

The other hot is doing the opposite. When the first hot is ramping up, the other hot is ramping down. When the first hot peaks at +170, the other hot peaks at -170. And so on. If you think of that picture of a sine wave for the first hot, the sine wave for the other hot is, literally, upside down from the first.

Snag a voltmeter. Read one hot to neutral: you get 120 VAC. Read the other hot to neutral: You also see 120 VAC. Now for the fun: Read from hot to hot and you'll see 240 VAC, twice the amplitude, because the difference between the two is 2X either of them to neutral. And that's how the A/C in your house gets 240 VAC to it: The air conditioning (or the wall connector on your Tesla) has two hots, with 240 VAC across them.

If you're math oriented, 120 VAC on the first hot is represented as 120 VAC @ 0 degrees, the other is at 120 VAC @ 180 degrees. Normal houses in the U.S. receive this kind of power which is called, "Two phase".

Fun. Now, three phase. For lots of very good reasons if one is trying to run a high power electric motor, things work a heck of a lot better if there's three or more phases. So, three phase power is pretty common. In fact, if one looks at high tension wires, one will often notice that there's three wires up there, and maybe another wire really high to catch lightning strikes. Yep, the power companies tend to play three phase, all the time.

So, suppose that one has three phases. Commercial buildings get this all the time. They like to light the lights in the building with 120 VAC, just like everybody else uses. So, at the entry to the building, you'll have a neutral (that's also bonded to ground at the building entry), and three phases of 120 VAC to neutral. These will be spread around 360 degrees. So, you'll have one phase, 120 VAC @ 0 degrees, then another phase at 120 @ 120 degrees, and a third phase at 120 @ 240 degrees. Let's call them phases A, B, and C.

Grab the voltmeter. Measure from A to Neutral, B to Neutral, or C to Neutral. You'll get 120 VAC each and every time, and that's the same voltage one can put a light bulb or computer upon, and that's what light bulbs and such get connected to in a commercial building. The Big Honking three-phase Motors that run the assembly line or the air conditioning system will (likely) get 120 three-phase (or bigger), but let's not worry about that.

The interesting question is, "What's the difference in voltage between phase A and phase B, or phase A and phase C, or phase B and phase C?

It's vector math. Let's take Phase A at 0 degrees and plot it on graph paper. 120 V on the X axis.

Next, take Phase B, use a protractor, and make a straight line from the origin to 120 degrees, length 120V. Go from the tip of that line to the +120 on the X axis, and the distance will be 208V - and that is what the voltmeter will read.

Doing a little math: (120 @ 0) - (120 @ 120) = 120 + j0 - (-60 + j103) = 180 - j103 = sqrt(180*180 + 103*103) @ 29.77 = 207.39 VAC @ 29.77 degrees.

The magnitudes of the voltages between phases will always be 207 VAC; the angles will be silly buggers that the voltmeter can't measure anyway.

The Tesla won't have a problem working off of 208 VAC on the two "hots" out of three, except that with 208 VAC and 48A the power into the car (the car is current limited) is 9.98 kW. At home, where one would have 240 VAC at 48A, the power input would be a bit higher at 11.52 kW. (Remember: P = V * I)

Now, just pulled up the Tesla Wall Connector installation book. Interestingly, it says that the Gen 2/Gen 3 accepts single phase power. Literally, it says, "Nominal 200-240 V AC single-phase". Which simply means that the voltage measured across the two, high-power wires going into this thing has to be between 200 VAC and 240 VAC. (Note: We're not talking about neutral, here.) Further on, we got the following:

1656346391279.png


So, note the terminology. "L1, L2/N, and Ground". That's interesting: So, suppose we got the three phase power in the building. Grab two of the phases, A and B (or A and C or B and C), attach to L1 and L2 and one is off to the races with 208 VAC.

BUT if one has, say, some kind of power system where there's 230 VAC to neutral, then they sure seem to imply that neutral had very much better be on the L2 connector, not the L1 connector.

Now, looking at @J.Kreed's commissioning post, that sure looks like a (slightly reduced in amplitude) two phases of a 120 VAC three-phase system. If one does the math (117.3 @ 0 degrees; 114.1 @ 120 degrees) then one gets a magnitude of 200.1 VAC, which is spot on. Hm. It is a trifle unbalanced, though: One would expect equal voltages. But not by a lot.

Thing is, the car will look for major unbalances and such with respect to ground and refuse to charge under those circumstances. Somehow, a difference of a little over three volts doesn't look like that much.

However, I have a different idea. It's well-known that if, as a Tesla starts charging, if the input voltage drops dramatically, the Tesla will very much stop charging, pretty much on the spot. This is a safety feature, as in, "We don't like to see houses/buildings catching on fire." Say one has a loose connection. On a good day, said loose connection might make incidental contact with the metal on both sides and have Low Resistance. Run lots of amps through it, nothing much happens. Might get a little warm.

On a bad day said incidental connection might have one or two ohms of resistance. Run 48A through an ohm, P = I * I * R = 48*48 * 1 = 2.3 kW at that resistive spot which is smallish in area and Flames R Us. The voltage will drop by V = I * R = 48 * 1 48V, so it'd go from 208 VAC down to 160 VAC.

So, you probably don't have an ohm of resistance in there. But you might have a hundred milliohms or something, your car sees the drop, goes, "Oh noes!" and stops charging.

All it takes is for on the several wire connections between the TWC, the breaker box, and the power transformer, is one not-as-tight-as-it-should-be screw.

No offense to anybody, but have the electrician come on back with his mini torque wrench and make sure everything is torqued down properly. As a first guess.

And, if I had to guess: Start with that slightly-low-voltage L2 phase.
 
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Few small nitpicks in an otherwise good explanation:

Residential is single split phase on the secondary (the neutral is tapped in the middle of the secondary winding on the transformer).
The entire electrical grid is 3 phase (HVDC and custom setups aside). Depending on the transformer type, you can go phase to ground or phase to phase to get your residential voltages on the secondary.
Voltages as low as 195V on 208V are common (especially in peak heating/cooling season), as are slight imbalances in the voltage of each leg, as it's tough to keep buildings perfectly balanced if there are lots of single phase loads.

I do agree that there might be a loose connection somewhere causing the voltage on one leg to drop dramatically. The car starts at 1 amp and slowly ramps up so the OP should be able to see the voltage drop on the car screen or with a multimeter if that's the case.
 
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Can you share a screenshot of what you see?
What would you like to see a screenshot of?

Sorry, I asked for a screenshot and then rudely disappeared for the weekend. What I was asking about was when you said this:

The screen in the car says its charging, However, all the charge stats at the bottom of the screen say zero.

Can you show us what the car screen says? I mean you said it says it's charging, but the stats say "zero", although you later posted something about it saying 236V, so I was wondering exactly what you were seeing.
 
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Sorry, I asked for a screenshot and then rudely disappeared for the weekend. What I was asking about was when you said this:



Can you show us what the car screen says? I mean you said it says it's charging, but the stats say "zero", although you later posted something about it saying 236V, so I was wondering exactly what you were seeing.
No worries! i appreciate it!

IMG_6103.jpg
 
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For all of those curious, we found the issue.
First things first, thank all of you who gave their input in attempting to help me. This was a great introduction into the Tesla community.

The building I work at has very old, and very questionable wiring. So, from the jump, i expected some issues from that.
The wall charger is wired into a sub-panel. But in reality, this sub-panel is pulled from yet another sub-panel (main sub-panel).
So, i bought the 60 amp two pole breaker, and all the other supplies for the install. After the install he told me to go ahead and finishing setting it up (the commissioning stuff). I said, you used the 60 amp breaker, right? He said, absolutely.
So i set it all up, and selected the 60 amp breaker.
It didn't work. After messing with it for a couple days, i finally posted here.
I showed all of your posts to the electrician this morning. After reading, he said "ill be right back".
5 minutes later he comes back to my office and tells me to try it again....and it worked.
So, when i set it up initially for a 60 amp breaker, it WAS actually wired to a 60 amp breaker. However, this entire sub-panel was ran off of a 50 amp breaker from the main sub-panel. So, the first time i tried charging like that, it "soft-tripped" the 50 amp breaker at the main sub-panel. The breaker didn't just trip and shut off like they usually do, it kept sending voltage but no amperage (I think, lol). So, as soon as he figured this out, he cycled the 50 amp breaker at the main sub-panel and told me to try it. I changed the commissioning option to 50 amp, and it worked perfectly. I ordered a 100amp breaker today to swap out that 50amp breaker in the main sub-panel. Then i can bump it up to 60 amps in the commissioning interface .

I still think its kinda weird that the wall charger or the car didn't immediately pick up on this issue. It was green lights across the board.

Thanks again everyone!
 
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Questions:
What happens if you plug your mobile connector into a 120V outlet
Your screenshot of the wall connector show 48A output, but the car says 40. Have you tried changing it in the app (try 12A at first, just to see what happens).
mobile connector works as well as supercharging.
Yeah, i did try every variation of the amperage options trying to get it to do something. That screenshot was when i had it set to 50 amps in the com interface. None of that worked. But, all is well now. Thanks!!
 
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For all of those curious, we found the issue.
First things first, thank all of you who gave their input in attempting to help me. This was a great introduction into the Tesla community.

The building I work at has very old, and very questionable wiring. So, from the jump, i expected some issues from that.
The wall charger is wired into a sub-panel. But in reality, this sub-panel is pulled from yet another sub-panel (main sub-panel).
So, i bought the 60 amp two pole breaker, and all the other supplies for the install. After the install he told me to go ahead and finishing setting it up (the commissioning stuff). I said, you used the 60 amp breaker, right? He said, absolutely.
So i set it all up, and selected the 60 amp breaker.
It didn't work. After messing with it for a couple days, i finally posted here.
I showed all of your posts to the electrician this morning. After reading, he said "ill be right back".
5 minutes later he comes back to my office and tells me to try it again....and it worked.
So, when i set it up initially for a 60 amp breaker, it WAS actually wired to a 60 amp breaker. However, this entire sub-panel was ran off of a 50 amp breaker from the main sub-panel. So, the first time i tried charging like that, it "soft-tripped" the 50 amp breaker at the main sub-panel. The breaker didn't just trip and shut off like they usually do, it kept sending voltage but no amperage (I think, lol). So, as soon as he figured this out, he cycled the 50 amp breaker at the main sub-panel and told me to try it. I changed the commissioning option to 50 amp, and it worked perfectly. I ordered a 100amp breaker today to swap out that 50amp breaker in the main sub-panel. Then i can bump it up to 60 amps in the commissioning interface .

I still think its kinda weird that the wall charger or the car didn't immediately pick up on this issue. It was green lights across the board.

Thanks again everyone!
Good detective work by the electrician, finding something that nobody here had thought of. Which is why he's an electrician and we're not 😁.

However: If the sub-panel is connected to a 50A breaker on the main panel (which is what I think you said), the implication is that the wires from the main panel to the sub are rated for 50A. (This is kind of a thing: If one has, say, a NEMA14-50 socket which one would normally have it hooked to a breaker whose maximum value would be 50A and to the wire between the breaker and the socket would also be rated for 50A.)

Putting a 100A breaker on a wire that's rated for 50A is kind of a no-no, as in Flames. Now, if a licensed electrician looks at the wire and goes, "Yup, that's the right gauge!" or goes and pulls a heavier wire on through, or whatever this licensed type does, then far be it from me to argue. But putting random Big Breakers on wires that aren't rated for Big Current is Bad Form.
 
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Good detective work by the electrician, finding something that nobody here had thought of. Which is why he's an electrician and we're not 😁.

However: If the sub-panel is connected to a 50A breaker on the main panel (which is what I think you said), the implication is that the wires from the main panel to the sub are rated for 50A. (This is kind of a thing: If one has, say, a NEMA14-50 socket which one would normally have it hooked to a breaker whose maximum value would be 50A and to the wire between the breaker and the socket would also be rated for 50A.)

Putting a 60A breaker on a wire that's rated for 50A is kind of a no-no, as in Flames. Now, if a licensed electrician looks at the wire and goes, "Yup, that's the right gauge!" or goes and pulls a heavier wire on through, or whatever this licensed type does, then far be it from me to argue. But putting random Big Breakers on wires that aren't rated for Big Current is Bad Form.
Good point! ill definitely ask him about this. Thanks!
 
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Weird. I wonder if it only tripped 1 of the 3 poles on the breaker and some motor load kept running on two of the phases and backfed power onto the other leg. Normally that f*^$ up equipment pretty bad, so hopefully nothing got fried.
The electrician checked everything out that was on the sub-panel, everything seems fine. I haven't noticed any issues on the charger or the car yet. It fully charged my car today at like 7 or 8 kWh.
 
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