it can be any voltage. its just the lower voltage the lower the power and the slower the charging. Most commercial buildings like hotels and office buildings have 208 volts instead of 240 volts. Any time i charge at a office building or hotel after voltage sag from charging i normally see 198-205 volts. You can ever charger from a standard bedroom nema 5-15 120 volt outlet and after long extension cords and voltage say it can be under 110volts.
There is nothing wrong with 231 (or even lower). Many destination chargers start with 208 and drop from that. The only concern is that extension cable appears to be rated for only 40 amps. You really need something rated for 50 or more.
You are not losing any costs. You pay for what you pull down. There is no potential for damage, assuming electrical wiring is up to spec. (FWIW this is the Model X forum, but the answer is the same).
Ambient temperature has negligible effect. Car can charge on anything from roughly 100 - 300 VAC, some configurations begin with 277 VAC
Awesome, thanks all. I'm limiting charging to 40A based on extension cable rating, but otherwise will just charge at 40A.
If you're worried about rating, you should be aware that North American code for continuous loads require de-rating the circuit to 80%. IOW, a 48A charge requires a 60A circuit and a 40A charge requires a 50A circuit. Assuming that the rating of the extension cable should be treated the same as the rating of a circuit, you should actually be charging at 32A regardless of what the juicebox is actually connected to. OTOH, if you don't want to worry about ratings (in spite of the fact that the exist for a reason), then I would guess that you should primarily be concerned about heat generated on the circuit, for instance, is either end of your extension cable going to get hot enough to melt anything?
Actually the 80% rule is mainly to determine the Circuit Breaker rating. If the "circuit" is 50 amps, by virtue of the circuit breaker installed (which so far has not been discussed). 40 amps through that cable should be fine. Although I would make sure any excess length, is not coiled up on top of itself, laying on the ground.
We also have to consider the rating for the wire.
I'm not saying you are necessarily correct or incorrect, but I'm not sure I follow your logic. Re: code, the circuit breaker should be sized for the lowest rated part of the circuit while the continuous load should be no more than 80% of the circuit breaker (which to translates to a continuous load limit equal to 80% of the lowest rated component of the circuit as opposed to the breaker itself since the wrong breaker being used doesn't magically make a higher load acceptable). Considering that, you are surely aware there were numerous 50A outlets connected to 40A circuit breakers melted due to the 40A continuous load caused by EV charging in earlier years. In terms of safety, with such incidents in mind, it might be wiser to treat the extension cable as part of the circuit and assume a lower circuit breaker amperage accordingly even if you are correct. To look at this another way, though, if you have a 5-15 extension cord rated for 15A and you connect a continuous load to it, it might be on a 15A breaker and should not have a contnious load in excess of 12A. Since that is what the extension cable is made for, I'm not sure why you think moving the 15A extension cable to a 20A outlet on a 20A breaker would magically make th cable designed for a continuous 15A load just because the outlet happens to accept 15A connections. However, this entire consideration might also depend on whether said extension cable is, for instance 14-50 or NACS/J1772 (or it might not if the cable should be considered part of the device, which then needs de-rated accordingly while the device shouldn't continuously draw more than 80% of what it is rated for, but that's way out in left field where I certainly haven't done any sort of studying). Good call re: excess length, though. My point with the heat on the extension cable (which could also be caused by coiling) was that it could cause vehicle damage, directly or indirectly, depending on formation we don't have, and a coiled extension cord could certainly cause a similar threat.
I assume it is being checked at the MCU or in the app. Is there really any reason to check it anywhere else at that point?
Does the extension cable also count as wire? Is this dependent on where the extension cable attaches?
I meant for purposes of the 80% rule.
First you determine your circuit, then based on the wiring and extensions, you apply the 80% rule to the lowest value
Particularly if your connection is an aerial drop. Arial drops carrying 200 amps, typically use 2 gauge aluminum wire (at least my area). 2 gauge aluminum wire is pretty lossy, but minimizing the weight of the wire is more important. If your connection is buried, the wire must be much larger, like 2/0 or4/0 to avoid overheating. Number 2 wire hanging out in the air allows it to effectively dissipate heat, although the voltage drop is much higher. Neither is a problem.
