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Aloha y'all. I know that a few smart, practical DIY minds are still firing here, gods and telescopes aside.
I'm going to wire 50 amp/240volt service from the house to a sub in a new garage about 70 feet away. I know there are wire gauge calculators everywhere, but I'm asking for an experienced opinion: AWG 6? SE cable? Aluminum?(please don't say aluminum).
And while it'll involve a nightmare of chipping (enough blue rock for a quarry) I'm thinking underground in conduit.
Any thoughts/horror stories/pieces of sage advice?
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Your going to need a licensed electrician,so ask them what is required.
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I would go with 3 x #6 THHN (+ 1 x #8 ground) in 1.25" schedule-80 PVC conduit.
I believe local code says 24" deep trench with 6" sand on the bottom (conduit 18" below grade) and another 6" sand over the conduit, with a flag (tape or wire) buried along the conduit.
Note1: neutral is NOT bonded to ground in a subpanel.
Note2: you have to go to Alpha for schedule-80 PVC.
Note3: while a 1" conduit is technically large enough for 4x#6, (a) sch80 has a smaller inside diameter (b) larger conduit makes for a much easier pull, and leaves room for expansion.
Note4: digging a trench is the expensive part -- lay a spare conduit so you don't have to do it again.
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And bam! Kinda knew you'd chime in, kalakoa, and I appreciate it! Love your input.
I know neutral and ground aren't (or shouldn't be) bonded in a sub, and I figured sched 80... But going Alpha? Ya got me there (as in, whaaat?)
Would lubricant help in 1" or just go 1 and a quarter?
Also, I trust your advice so I'm gonna ask- is a 24" trench worth it (you don't know my pahoehoe, it was burped up by someone in a foul mood)? Would you go poles for 70ish feet?
No more questions... Thanks much!
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X1 on Kalakoas post. Believe local code won't allow for your application, so "red flag" to the inspector driving by, unfortunately. "Goop" is good as the 90* bends bind up the conductors quick. Larger diameter means easier pulI. More room for additional conductors but then you really have to goop up to prevent chafing the other conductors already in place. Bury a twin along with it sans conductors, maybe a small one for low voltage, computer cable, eric.? Believe Kalakoa was referencing the Alpha Electrical Supply on Holumua in Hilo.
Community begins with Aloha
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Aha! Thanks Tink.
The twin conduit is definitely a good idea (now thinking of low voltage apps).
I've had folks recommend UF cable, but I'm leaning THHN/conduit for safety and versatility. I'll probably never draw 50 out back, but I like the ability so #6 it is. Also not worried about drive ups ¯\_(#12484
_/¯
Y'all are great. Mahalo!
Now the hammering... God, the hammering.
