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I need to run power to a shed 75 ft away, sizing for 20 amps maybe 30 surge.
I'm thinking of going with 10/3 direct burial cable in metal conduit buried 8 inches or so in ripped pahoehoe and backfilled with cinder and gravel.
Two questions: Is this the right approach? Where can I get the cheapest cable and conduit?
All suggestions welcomed.
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I recommend plastic conduit underground.
Assume the best and ask questions.
Punaweb moderator
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PVC conduit is easier to work with, doesn't rust, and can be made watertight.
The schedule-80 is strong enough to drive on (but not available at Depot, go to Alpha).
Direct-bury cable is overkill unless it's actually being direct-buried. Pull some nice THHN.
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My garage is 150 feet away from the house and has 220v ran to it, down about 12-14" in PVC (not schedule 80) in previously ripped and cinder covered yard. I couldn't tell you what the wire size is though. I wanted to be able to have a decent sized air compressor and use a welder. The electrical addition was permitted. In hindsight - do not build your garage/workshop that far away from the house. It sucks when the tool you want is way over there and it is raining.
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Thanks for the info guys. Anywhere local with good prices on THWN? Or the twisted "submersible pump cable"? Looks like Amazon is ~$.33/ft/conductor
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Home Depot 500' spool of #10 stranded is $106. Solid is $82. Get black wire and some colored tape.
ETA: Home Depot seems to have better prices than Amazon.
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Huh, I did not see #10 solid at our Hilo store. Can I use stranded for 120VAC?
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Absolutely. It's a bit more expensive but easier to work with.
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Can I use stranded for 120VAC?
Stranded works well for both AC and DC.
Get black wire and some colored tape.
Heat-shrink tubing is much cleaner -- unfortunately Depot has a limited selection. The adhesive-lined variety makes for a lovely splice. Best (portable) tool for the shrink is a small butane torch ("crack lighter").
I did this many times: unspool the wire to make a bundle, tag the ends with heat-shrink, pull the finished bundle through conduit. A little more work, but cheap, and you can make up whatever configuration you need at the time.
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Is there clear heat shrink tubing?
Googled it and there is. Get white wire, colored sharpies, and clear heat shrink tubing?
