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Suppose I have a duplex, building A, which has 2 electric services. It also has a detached garage structure, building B. Each tenant has half the garage. Weirdly, garage lights are powered from the house of a cooperative neighbor so are on neither service. That is the only service to the building and it cannot possibly carry EV loads.

Now, with EVs arriving, each tenant wants an EV charge station, and they understandably want it powered off their own meter.

How do we make that work legally per NEC? It seems like we will have 3 services to the building. Will we be forced into a new service there and doing "pay stations"?

Can the alien services come into the building if they only serve a hard-wired EV station?

Will it help if the EV stations are standalone stands just outside the garage? (It doesn't have doors anyway).

Harper - Reinstate Monica
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    I do not plan to self answer. – Harper - Reinstate Monica Nov 17 '23 at 01:07
  • *230.2 (D) Different Characteristics - Additional services shall be permitted for different voltages, frequencies, or phases, or for different uses, such as for different rate schedules.* would seem to allow for **one** of these because it is 240V, assuming the lighting circuit is 120V (and just a circuit, no panel in or on the garage). A bit of a twist would be to say make one of the circuits 240V/120V but AFAIK all reasonable EVSE are 240V-only devices. Another unlikely solution would be if the two EV users happen to have different Rate Schedules, but that's unlikely. – manassehkatz-Moving 2 Codidact Nov 17 '23 at 01:28
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    "Lights powered by a cooperative neighbor" actually sounds like a violation, as tenant services are not suposed to supply power to shared/community spaces – Ecnerwal Nov 17 '23 at 02:29
  • @Ecnerwal yeah, I reckon it is, _however_ migrating the lights to a house panel wouldn't change the underlying question – ThreePhaseEel Nov 17 '23 at 03:10
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    @manassehkatz-Moving2Codidact -- this would be an Article 225 situation not Article 230 most likely since I reckon the service drop/lateral isn't landing in the garage – ThreePhaseEel Nov 17 '23 at 03:12
  • If the EVSEs are on stands **outside** the garage, could they not be considered part of the garage structure? I don’t know if this is possible, but if it is, could the garage be ignored and the stands be considered little different than light posts? Two posts that happen to be near the garage, are fed from underground conduit from each home, and carries an EVSE instead of (or along with) a light. – DoxyLover Nov 17 '23 at 06:04
  • Is this a hypothetical or actual question? Hypothetical questions are technically off-topic... – FreeMan Nov 17 '23 at 13:28
  • Also, why not cut off service from the "cooperative neighbor" and have each tenant also light up his half of the garage along with powering his own EV. – FreeMan Nov 17 '23 at 13:31

1 Answers1

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I would call this OK but it depends on your AHJ's interpretation of "different uses"

NEC 225.30(E) permits a structure to be fed by multiple branch circuits or feeders that have "different uses":

(E) Different Characteristics

Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases, or for different uses such as control of outside lighting from multiple locations.

I would call two separately metered tenants in the garage "different uses" myself. However, I am not sure what AHJs think of such a setup, as power to garages has not needed to be split among tenants like this until now.

Note that you'll need a local disconnecting means for each branch or feeder to the garage to comply with 225.31, as well as a grounding electrode system at the garage tied to the equipment grounding conductors of all the branch & feeder circuits at their respective disconnects. (The good news is that since EV chargers don't use neutral, you can use bog-standard non-fusible air conditioner pullouts for the EV charging circuit disconnects.)

ThreePhaseEel
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