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Adding EV charging into my PV/ESS setup

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I can't resist jumping in with a question about disconnects. But if you put a 100A circuit that contains EV chargers; would you need to put a disconnecting means within line of sight of the chargers under CEC 625.43? Or does that rule only care if an individual charger is 60.0000A or above?

PS, I want H2ofun to go get a 9th disconnect.
The breakers in the subpanel are within line-of-sight of all of our wall connectors. They used a subpanel that doesn't have a cover, so the breakers are always visible. (See subpanel on the right in post #7 above.) Admittedly, you'd need really good eyesight to see them from the farthest wall connector.
 
my two 200 feet 6/3 romex from my inverters to generation panel are 60 amp breakers so is this not okay for 60 amp ev chsrging.
6/3 NM has an ampacity of 55A. That is not a standard breaker size. So when the calculated required ampacity is 55A or less, you can protect it with the next size up breaker, 60A. But if the calculated required ampacity is 55.1A to 60A, you can't use 6/3 NM.

So a 44A (continuous) EVSE has a required ampacity of 55A (125% for continuous loads), and you can use 6/3 NM for the circuit, with a 60A breaker. Likewise for an inverter with maximum continuous output current 44A or less. But a 48A EVSE would require different wiring for use on a 60A breaker.

And as a side note, other wiring methods will have a higher ampacity than NM cable, for a given size. That is because NM is restricted to the 60C ampacity (the allowable current is based on the insulation being able to withstand temperatures of 60C), while other wiring methods may be able to use the 75C ampacity. [This usually only starts to matter at sizes #8 and larger, due to another rule.] #6 Cu has an ampacity of 65A at 75C, for example, so if you use 6/3 SER (if it exists) or MC cable, or used most any conduit method, you could still use #6 Cu conductors on a 60A breaker for a 48A continuous load.

Cheers, Wayne
 
I get your need (obsession ?) to future proof, I am same way.. but if you have zero ev‘s now seems extreme to plan for 3 in a complex way .. if I read correct @MorrisonHiker actually has 3 activley used ev’s .
My point is you would be surprised how useful even a single Tesla connector (gen 2 with “longer” cable) can be. I installed mine with the intention of charging one model 3 .. perhaps a second ( or model Y) .. with the thought the cable can easily reach to middle spot in 3 car garage. Since having my connector for past 1.5yrs I have charged friends’ Teslas in garage middle spot and in driveway, and even an almost complete stranger when I was not home (friend of a friend traveling ) with garage door open just few inches to allow cable to driveway ... but yes having 3 connectors in garage etc looks really cool and if actually using multiple EV regularly is more convenient
Anyway if it were me I would run single 100amp breaker / appropriate sized cable (read up on THHN in conduit vs Romex for continuous loads). This would allow you to now use a single Tesla connector with minimal “waste” or daisy chain 2-3 gen 2 connectors (yes you need comm cable, easy compared to main cables ) I am not sold on gen 3 connectors seem issues with software / WiFi / what they will do vs can do now.. etc but maybe they have improved
(this all assumes you will purchase a Tesla(s) .. but I’m sure your 100amp 240v circuit could be used in some way with most any EVSE(s) )
 
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As to the question of adding multiple EVSEs, by "output" of the Gateway you mean the PW side? Then without further controls, if the grid fails while your EVs are charging, they will happily continue to charge until your PWs run out. Even with (5) PWs, the EV may have a bigger battery. An argument for powering from the grid side of the Gateway (or otherwise automatically killing power to them when the grid is out, perhaps with a manual override).

Loads on the PW side of the Gateway are restricted to 200A, or less if the grid supply to the Gateway is smaller. So you would need to do a load calc to see if you have capacity to add (3) 60A EVSEs. What category to put an EVSE in for a residential load calc (i.e. what factor to use on the load before summing) is a little unclear to me, but they would count at least at 40%, or 72A out of the 200A (or less) available.

The same calculations apply on the grid side of the Gateway, but the available power may be higher, depending on the details of the service and feeder.

Cheers, Wayne
 
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