Tesla Gen 3 EV Charger

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nizak

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A couple questions for anyone familiar with the Tesla Gen 3 charger.

- 1.I see that the charger can be wired to a variety of different amperage’s depending on what length of charge time.

48 A is the highest and requires a 60A 240 V feed.
Install info states #6 Cu 90 degree conductor.

Am I wrong in saying #6 NM cable (55A)can be used if terminated on the next size up (60A) breaker?

2. Install info states cord and plug connection not allowed.
Is that only for the 60A rating ?

50A rating would be a standard range cord and 14-50 receptacle.

Thoughts?

Thanks
 
nizak said:
Am I wrong in saying #6 NM cable (55A)can be used if terminated on the next size up (60A) breaker?
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Yes, you are wrong, if you intend to set the unit at 48A charging.

You can only use the next size up rule when calculated circuit current is equal or less than the wire rating. In this case, because it's a continuous load, the required ampacity is 48×1.25=60 so you may not use 55A rated wire.

Also, it would be a violation of the instruction manual, which requires 90C wire.

You could probably use MC cable instead of NM.
 
jaggedben said:
Yes, you are wrong, if you intend to set the unit at 48A charging.

You can only use the next size up rule when calculated circuit current is equal or less than the wire rating. In this case, because it's a continuous load, the required ampacity is 48×1.25=60 so you may not use 55A rated wire.

Also, it would be a violation of the instruction manual, which requires 90C wire.

You could probably use MC cable instead of NM.
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or, depending on the Code cycle, SE cable.
 
As far as cord and plug... Tesla's come with cord and plug for up to 32A charging. So pretty much the whole point of the wall unit is to exceed what cord and plug allows.
 
I have been using aluminum SE and SER cable for chargers, generators, large appliances. etc.
 
Am I wrong in saying #6 NM cable (55A)can be used if terminated on the next size up (60A) breaker?

A lot of folks get tripped up by that as it is a true statement based on Art 240.4 but, as noted above, you also have to take 210.19(A)(1) into account:
"(1) General. Branch-circuit conductors shall have an ampacity not less than the maximum load to be served......................................"
 
It’s the longest run possible for the branch circuit.

From one end of the basement to the furthest point of the attached garage wall the charger is mounting on.

Going to use Al SE cable and j box the last 5’ to the charger with Cu THHN.
 
nizak said:
It’s the longest run possible for the branch circuit.

From one end of the basement to the furthest point of the attached garage wall the charger is mounting on.

Going to use Al SE cable and j box the last 5’ to the charger with Cu THHN.
Click to expand...
Go with an AC disconnect it'll be cheaper and comes with its own dualrated splices
 
If I’m reading 625.43 (2017) correctly no disconnecting means is required for an EV charger as long as its 60A or less and no more than 150V to ground?

So circuit breaker directly to charger termination is it?
 
nizak said:
If I’m reading 625.43 (2017) correctly no disconnecting means is required for an EV charger as long as its 60A or less and no more than 150V to ground?

So circuit breaker directly to charger termination is it?
Click to expand...
Not required but a good idea. A Cheap ac disconnect is less than the splices themselves when transitioning to copper from aluminum.
 
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