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Wire size: Nailed it. #1 Aluminum is the minimum allowable size given the 100A breaker supplying it. You are required to provision 125% of headroom on planned loads, so you shouldn't plan to draw more than 80A on a regular basis. Since you know your practical load is 60A, you should compute voltage drop on that basis (not breaker trip). At 60A, ...


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Your choice of 1-1-1-3 Aluminum is adequate. Most Level 2 car EVSEs only draw 30-32A continuous. A few years ago I dropped 2 gage Cu from my panel to my car charger spot. It was way overkill for my 32A ChargePoint, but just a couple years later and we have 40A and 60A EVSEs available. I could put two Tesla Wall Connectors on that wire and only need to ...


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The subpanel is the way to go. But make it big! That is our #1 thing on panels - you want lots of spaces. Spaces are cheap, regrets because your panel is full are expensive. And that is a dinky little panel downstairs, you're not going to get much out of it, and I bet you're already double-stuffing that! Of course you want a small "box size", but that ...


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Conduit is still your friend Even though running rigid EMT back to the main panel from the basement junction box is basically impractical with all those other cables in the way, it is still possible to stay in conduit all the way back to the panel. How? Flexible conduit, that's how! In particular, instead of running a cable (or cables) back to the panel, ...


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Normally you're not allowed to mix service wiring and branch circuit wiring, but solar is special. Derating It's almost never a problem with 2-3 circuits, but when you put 2+ circuits in conduit, you must pause to do a "derate" calculation. Other rules prevent you from using wires at their thermal maxima, but you derate off of that. For THWN-2 wire, ...


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How many current carrying conductors total? More than 3 and you have to start derating per table 310.15.B.3.A So it may be worth it to have separate conduits. Since you have micro inverters you already have 240 ac , the code really focuses on dc connections for pv systems as the ac is standard and you still have the same rules. The requirements are spelled ...


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I'd scrap this whole plan and start over (save for the existing buried conduit) You started off on the right foot by burying a conduit from the house to the shed, and you are also correct that NM is nogoodnik in a wet environment, so we'll be replacing that as you indicate. However, you were only familiar with the cables (NM and UF) used for building ...


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You broke the first rule of buying wire: buy it after you talk to StackExchange. Unfortunately you may have to sell this cable on Craigslist. This went off the rails quite awhile back I mean this never had a chance, and I have no idea where you got your advice (Home Depot) but you were fantastically misled. Here. I actually plugged your cables into ...


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Derating doesn't prohibit rounding up The rule that lets you "round up" nonstandard breaker trip requirements to the next higher standard size is NEC 240.4(B): (B) Overcurrent Devices Rated 800 Amperes or Less. The next higher standard overcurrent device rating (above the ampacity of the conductors being protected) shall be permitted to be used, ...


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YES. I can't vouch for what "3-wire set" means. I suspect it only made sense in context of that other question (you didn't get it out of NEC). Cable in Conduit: Yes actually, but it sux You ARE allowed to run cable in conduit, in two modes. You can either use it as physical armor only (for which sched 40 PVC is inadequate), or you can use it in the ...


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Easy. Place a thin-yet-protective sheathing around your new wire's existing cable sheath. Then slide the extra-protected wire into the opening without and worries; the little scratches won't even cut into the cable sheath. Sturdy, but stiff: small-diameter pvc tubing Sturdy yet flexible: thin plastic tubing made for aquariums. Go to your local pet store for ...


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