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Home Backup using 240V from CT Vault, would this work ??

CybrTrkNj

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Afternoon,
Since the Powershare 3V Gateway installs are crazy priced, I was wondering if this setup would work?
All manual, no interlock. DANGEROUS if NOT paying attention.
Normal situation (no outage)- use the Uni Wall Connector to charge Cybertruck. NACS connected to CT, NEMA 14-50 outage cable not connected to anything.
Outage situation - kill MAIN breaker, disconnect NACS from CT, connect NEMA 14-50 outage cable to 240V outlet in vault, turn on CT outlets.
Outage over - turn off CT outlets, disconnect NEMA 14-50 outage cable, turn on MAIN breaker, reconnect NACS charging cable.
The possible simplicity of this design (doubt NEC compliant), is the double use of the wires from the 60A breaker.
Please review the attached drawing and let me know if anyone sees any potential issues.
Side note: the NEMA 14-50 outage cable will have it's plug covered and stored out-of-site when not in use. No exposed live prongs on plug.
Will this work, or am I batshit crazy ?? MY main concern is the NEUTRAL connection.
Thanks !

Tesla Roadster 2nd gen Home Backup using 240V from CT Vault, would this work ?? OUTAGE
 

SSonnentag

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Neutral and ground are tied together at the panel. Actually, they're separate bus bars in the panel, but they're tied together by the metal box itself. I think you'd need to pull power from the NEMA 14-50 plug in the bed instead of from the NACS plug. I'm guessing it takes some sort of software handshake and communication between the HPWC and the truck in order to activate reverse power flow via the NACS port.

Edit: I guess I should not only look at the diagram, but read too. I don't see any problem with your idea, other than the county not liking it. As long as the main is disconnected you're good. Just don't forget to disconnect the truck before switching that main back on. :)

Edit 2: Also, if you have solar, you'd want to throw the inverter disconnects as well.
 

Carlos Thomas

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I have a Interlock Kit, Generator Inlet Box and a RV/Generator 50 ft cable. The install of the Generator Inlet Box, New Breaker Switch with a Interlock kit was $500 installed with a permit. The cable was $279. So all in I was less than $800. Ready for the next power outage.
 

MICyber

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jameskk

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yes a lot of people are doing this, including me. Unfortunately my electrician has stood me up for two appointments now.
 

Jager

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Utilizing the Cybertruck's 240v bed outlet to provide emergency home backup power is very straightforward, and something that a lot of us will be doing because of the outrageous quotes coming out of Qmerit.

But backfeeding into the panel is both illegal and extremely ill-advised. For good reason.

Use a transfer switch. Or use an interlock. People running generators have been doing this forever. It's not hard. And it's not particularly expensive.
 
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