Wall connector amps question

[MOWDEL3]

I had my wall connector installed by a friend who is a sparky but has not done one before. When I was commissioning it, I asked him how many amperes and he did not have a clue. I just put in 32a. The breaker says 16-32a

If the cable is not connected, the app says maximum amps at my location is 16amp. While I am charging, it says 32amp. It went from 77% to 89% in 1 hour. Which if I am doing my calculations correctly is around 7.2 kwh.

Is my calculation correct?

 

[MOWDEL3]

Screenshots

 

[Onshore]

Post a pic of your breaker.

Second screenshot suggests you're getting 32A, which is 7kw, the highest setting for single phase power.

 

[Punchbuggy]

7kW is about right for a 32a feed. I'm not clear why it restricts the setting to 16a when idle in the app though. I'm able to select up to 32a on mine.

Otherwise, noting that you're charging up to 100%, I assume you've a Chinese-built Tesla with LFA batteries (which is likely given your join date here).

 

[locksmack]

Your mate should definitely have a clue whether the circuit he installed can handle 32A. I'd be concerned he hasn't used thick enough wire...

 

[MOWDEL3]

Yes, it’s a Chinese built one with the LFP battery. I am on single phase. The breaker is the orange one

 

[locksmack]

Yes, it’s a Chinese built one with the LFP battery. I am on single phase. The breaker is the orange one

That breaker will be fine for charging at 32A, but as with my previous comment - I'm concerned that your mate didn't know, which makes me question the install. Do you know what size the wiring is (2.5mm or 6mm probably?) and the run length?

 

[MOWDEL3]

The wall connector is just below the breaker, probably less than a meter. What size wire should he have used? I’ll ask him

 

[locksmack]

The wall connector is just below the breaker, probably less than a meter. What size wire should he have used? I’ll ask him

Probably 4mm or 6mm - but I'm not an electrician or qualified to give advice on that.

 

[blubbernator]

This does not look compliant to the latest revision of AS3000 to me, however it would have been before. He should have used 4mm at minimum, depending on the cable type (TPS vs V90) even 6mm and all final subcircuits need to be RCD protected now. I would have installed a 40A RCD/MCB combo and a 6mm cable, as the 32A load is constant. (I am a Electrical Nominee).

 

[bay74]

The weird 16A limitation isn't just in the app. On the screen in my Tesla I can't select more than 16A until it starts charging, if I previously had charged at lower than 16A (at this location). As soon as it starts charging it seems to realise that it could go up to 32A. Mine's a 2019 so not LFP batteries.

 

[locksmack]

The weird 16A limitation isn't just in the app. On the screen in my Tesla I can't select more than 16A until it starts charging, if I previously had charged at lower than 16A (at this location). As soon as it starts charging it seems to realise that it could go up to 32A. Mine's a 2019 so not LFP batteries.

Yah the 16A thing is normal - mine is the same.

 

[[Zombie]]

16A is the limit for three-phase (which gives ~11kW) so it's likely the car assumes it will be plugged into a three-phase supply until it can confirm.

 

[doggy1]

16A is the limit for three-phase (which gives ~11kW) so it's likely the car assumes it will be plugged into a three-phase supply until it can confirm.

This is usually the case. However, right now after a day's charging on single phase, my phone app is saying 48Amps! I charged up to 17A during the day. The 48A is probably a reference to the USA with 48A and 120Volts. Or it is thinking 3 phase and 3x16=48A. A trifle bizarre. However, in the past when it has said 48A, it has reduced to 32A or lower when I actually started charging (depending upon how I set my OpenEVSE).

 

[MOWDEL3]

This does not look compliant to the latest revision of AS3000 to me, however it would have been before. He should have used 4mm at minimum, depending on the cable type (TPS vs V90) even 6mm and all final subcircuits need to be RCD protected now. I would have installed a 40A RCD/MCB combo and a 6mm cable, as the 32A load is constant. (I am a Electrical Nominee).

He used 4mm TPS. It does seem that I’m getting 32A. What kind of problems do you see with the way he did it? I might ask him to redo it

 

[locksmack]

He used 4mm TPS. It does seem that I’m getting 32A. What kind of problems do you see with the way he did it? I might ask him to redo it

4mm is probably fine.

I've seen conflicting reports about the breaker size. There is definitely a rule in the US where breakers need to be oversized by 20%, but despite numerous people saying the same in Australia, I haven't seen any documented proof of such a requirement. My electrician also installed mine with a 32A breaker, and I have been charging for about a year without issue.

An undersized breaker shouldn't cause any safety issues as it will just trip earlier.

Disclaimer: Not an electrician, don't use anything I say as advice.

 

[Gareth Oakes]

If OP would like peace of mind then they could fiddle with Jcalc to determine if 4mm2 is sufficient for the installation Cable Size Calculator AS/NZS 3008
Personally I would have opted for 6mm2 cable for 32A, unless it was a short run, but I'm no electrician!

 

[joeljesudossu]

Hi, I am a new 2023 Tesla Model 3 Long Range owner. Had the car for about two weeks.

I have a question on charging. I need to set the home charge cost to $0 since I have Solar and I pay a flat connection fee of $35 per month. Since I am always producing excess electricity than what I consume. So I figured charging at home would be $0.

However the Tesla app doesn’t allow me to set it to $0. I am required to set it to atleast $0.01 per KWH

Could someone please advice on how I can go about this. The only workaround would be to set it as $0.01 per KWH and ignore the cost. Ideally it would be better if I set a flat cost of $35 per month. Or let me know if there is a better way.

 

[cafz]

Could someone please advice on how I can go about this. The only workaround would be to set it as $0.01 per KWH and ignore the cost. Ideally it would be better if I set a flat cost of $35 per month. Or let me know if there is a better way.

I have the same problem, because I'm on the Red Energy EV tariff that has free electricity times. It was previously possible to set a $0.00 rate, but an update to the app last year imposed the $0.01 minimum, so I've been using that workaround since then.

However in your case, the real cost of charging is the feed-in tariff you're forgoing by using that electricity to charge instead, so just put your feed-in rate in as the cost.

 

[bay74]

Ugh the weird 16A indicated limit bit me. Plugged in car, increased charge rate to 16A, as that’s the max’ it allowed (erroneously as noted above), but when scheduled time came, car increased the 16A I set to 32A. I guess that it interpreted my input 16 as “max” which is wrong. There should/could be a “max” entry, above 16A, or the car could just properly allow setting any allowable value.

I usually don’t use 32A as the voltage drop is considerable (like 20+V).