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Overclocking j1772, 200 amps on tesla plug

I have a unique problem, I want to plug in a vehicle that can pull 200amps ac however I don’t really want to build a full ocpp compliant system. How can I signal more amps? One idea is to increase the pwm frequency. Make 2.00 khz 1000 amps an 1.08khz 80 amps. that way old cars just see 80 amps.
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@Eli, Tesla did not just pump 900 amps.  They did that with temperature sensors as a backup.  The electric codes are conservative to give margin: what Tesla is doing requires temperature sensors to be safe, and the ability to reduce current at any time to manage heat.

Tesla says they tested 900 amps with an uncooled inlet. Not sure why this is unwise. The wires that feed homes handle 200 amps without any temp sensors

J3400 NACS cables have a thermal sensor option.  That can be used to push the limits on wire ampacity.  That said the goals in this post are unclear, and seem unwise.

Missing the point? "I want to plug in a vehicle that can pull 200amps ac" . The point was certainly not clear.


For non-EV use just use the connector. No need for any pilot signaling. An appliance or tiny house would not be able to control load like a DC onboard charger on an EV can.


J3400 NACS cables and connectors are not cheaper than NEMA 14-50 RV plugs. The OpenEVSE product uses both. Our NEMA 14-50 "RV" Input cords cost less than $50 to manufacture and 3400 NACS cost more than $150.

You are missing the point, not for vehicles, for appliances, tiny houses, solar panels systems etc. needs to be cheap and simple. J3400 connector is already cheaper than rv plugs and extension cords will likely be cheaper by the end of the year. I’m testing 10gig fiber internet on the data pins also, its a very compelling platform. Just need a simple fallback for low cost endpoints

Hi Eli


It is a very unique problem, most homes across the globe can not support this amount of Amperage. You would likely be much better off moving from single phase high current to three phase at a much lower current. There is already a 3 Phase 63A standard which could get you up to 45kw.


You will need custom firmware and hardware on both the station side and vehicle onboard charger. 


There are no vehicles that have onboard chargers that can handle this amount of AC power and convert it to DC for the batteries. You will need to develop a monster onboard charger for this.


You will likely need a custom socket and custom charge handle as well. The wire size to handle 200A is huge. Going to 3 Phase would help and switching to DC at battery voltage would help too.

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