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drysart t1_ja3vr7w wrote

I had a discussion here on reddit back in September (about two weeks before Tesla announced their new 1000V plug variant) where I went over specifically what limits their plug to 500V, and concluded it was primarily the airgapped distance between their high voltage pins, not the size of the pins themselves.

If you look at the technical specs that they ended up releasing two weeks later where they introduced their new 1000V-capable variant, you'll notice that the most noticeable change between the 500V variant and the 1000V variant (see pages 16 and 21, specifically), is that they've recessed everything relating to the HV connections back into each side of the connection about 5mm; which adds about 10mm to the airgap, which is more than sufficient to safely extinguish a 1000V arc before it can bridge the pins.

Notably, though, the thickness of the pins themselves is unchanged in the 1000V variant. I'm not going to do the math right now but I wonder if that pin gauge is what holds their new connector design back from being >1000V capable because increasing the airgap alone should buy them plenty of safety headroom (but I'll also admit I'm not intimately familiar with the necessary safety margins they'd be aiming for).


Zorb750 t1_ja43z20 wrote

Well, the size of the pins is never going to have anything to do with voltage. Voltage ratings are always a function of insulation, whether that is in the form of an air gap, some sort of dielectric material like wire insulation, even the dielectric properties of the material the connect your body is made of.

I'm going to read over this. Remember that there are plenty of very thin conductors that carry high voltages. The pin size only needs to be able to handle the amperage, as well as having reasonable properties against wear. In fact, one of the reasons that higher voltages are often used in a DC circuit, is to allow more power capacity with a given size of conductor. Look at Qualcomm with quickcharge 2 and 3. Your normal USB cable is good for roughly 2 amps, maybe a little bit more, so you can't increase the amperage beyond that, but you can drive up the voltage and just use a buck converter in the phone. That's also why those phones get so hot when they are charging.


Zorb750 t1_ja60jt9 wrote

This is actually pretty interesting. I read over your couple of pages you sent me.

As far as safety margins, I'm not sure. I know that the highest I have ever seen on mine was in the low 400 volt range, but I also know the newer Model S has a 500 volt configuration, and the model 3 is approximately 350 volts. I know that they wouldn't run the connector right up to its tolerance, or I think even within 25% of it. That with the model 3 is part of what really surprises me, though. I'm not sure how they are pulling that off, if maybe the model 3 connector is slightly different of the car end. I have looked at mine in detail obviously, but it's old now. I'm still somewhat impressed every time I see much over 100kw (seen low 120s), at over 300 amps at 400 volts. I don't use the supercharger often, though.