Underground electrical question
#17
  Re: RE: Underground electrical question by fixtureman (Why not put the ell ...)
(08-04-2020, 07:10 AM)cams2705 Wrote: Do you actually need power inside the shed?  If not, why not just pull new wire as another poster above suggested, but to an exterior box mounted on the side of your house with a GFCI and not worry about running anything underground.  You can use an extention cord when you're out there an need power.
This.  Assuming the shed is considered "temporary" or "portable" (whatever the word used in the Code is for it) I did something similar for my former garden shed, now spray booth/welding booth.  I put a 50 amp RV outlet on the outside of my shop shed and in the SB/WB shed, I permanently wired to a small breaker panel a short 50 amp RV extension cord with a plug on the end.  I did that so that the county can't come along and say it's permanent, since it is a small enough shed on skids to meet the definition.  Instead of an extension cord, I'd put in something permanently wired inside the shed that you can plug in to your house when needed or leave it plugged in all the time.  

 
(08-04-2020, 11:47 AM)fixtureman Wrote: Why not put the ell at the roof and the into the shed.

Or this.  If you want to keep the shed permanently wired in.  It may be a head banger issue, but if you don't have to go between the house and the shed too often, it should not be an issue.  It looks well protected, wrap some foam pipe insulation on it should minimize the damage from forgetting to duck.  I am not sure an outlet would be useful in that tight of a space, but you could still drop a conduit down and feed an outlet on the side of the house as well.
Paul
They were right, I SHOULDN'T have tried it at home!
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#18
  Re: Underground electrical question by chrisntam (Working on my shed, ...)
Thanks for all the replies, they are appreciated!

The shed has outlets and an 4' switched light fixture, I'll keep the shed energized.  I'll put it in the ground as I do go through there from time to time.  I'll prolly keep it on the diagonal, however deeper, due to the existing holes in the soffit and shed siding.  Did not think about a GFCI, will install that in the shed as well.

As always, advice and ideas here are appreciated!

chris.
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#19
  Re: RE: Underground electrical question by chrisntam (Thanks for all the r...)
(08-04-2020, 01:54 PM)chrisntam Wrote: Thanks for all the replies, they are appreciated!

The shed has outlets and an 4' switched light fixture, I'll keep the shed energized.  I'll put it in the ground as I do go through there from time to time.  I'll prolly keep it on the diagonal, however deeper, due to the existing holes in the soffit and shed siding.  Did not think about a GFCI, will install that in the shed as well.

As always, advice and ideas here are appreciated!

chris.

That means you need more cable someplace.
Suggest you consider Cams2075’s idea.

Add a gfci at the bottom of the emt. Everything downstream will be protected.   Use appropriate gauge uf cable from there.   Stubbing it would only cost an extra $5   (edit: only about $2.50 if you re-use the 1/2“ conduit you have, then you only need an LB @$1.68, and two male fittings at 30¢/ea).  If you stub it the conduit is not considered a raceway and the 53% fill restriction does not apply, so you may get by with 1/2” pvc.  If it is closed at junction boxes on both ends it is a raceway.


If ever inspected, you could argue
1. the emt is not a raceway, but a sleeve
2. the nm in the conduit is permitted because the conduit is protected by the two roofs, and hence not a wet location (would probably lose with my inspector, but who knows. You definitely lose if the nm  is buried).
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#20
  Re: Underground electrical question by chrisntam (Working on my shed, ...)
I would tear out all existing up to the attic.  I'll tie on the existing romex in the attic with a J-box.  THWN from there through the new conduit to the shed.  GFCI at the first connection from the THWN.

What is EMT?

I'm not overly worried about cost, I'll get all new cable, conduit, fittings, etc.  I like the larger 3/4" conduit, easier to pull the wire through...  Do I need to lube the wire?  It'll be going through 3 gentle 90s.

It won't be inspected, but I want to do it right.  It'll be a wet location since I'll have a soaker hose there.
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#21
  Re: RE: Underground electrical question by chrisntam (I would tear out all...)
(08-04-2020, 03:10 PM)chrisntam Wrote: I would tear out all existing up to the attic.  I'll tie on the existing romex in the attic with a J-box.  THWN from there through the new conduit to the shed.  GFCI at the first connection from the THWN.

What is EMT?  Electrical metal tubing... that lightweight conduit stuff most often used.

I'm not overly worried about cost, I'll get all new cable, conduit, fittings, etc.  I like the larger 3/4" conduit, easier to pull the wire through...  Do I need to lube the wire?  It'll be going through 3 gentle 90s.    If pulling thwn 1/2” is plenty big.  Even with three 90° it should be an easy pull.  Just make sure you have the conduit bells pointing in the right direction for the pull.

It won't be inspected, but I want to do it right.  It'll be a wet location since I'll have a soaker hose there.  Any underground is a wet location, regardless of the soil moisture.  The wetness will come from the humidity in the air.  The soil 18” below grade will be cooler than ambient.  Anytime  that underground temp is lower than the dew point of the outside air it will condense the water vapor inside the conduit.   A few drops here, a couple later on... After a few months of really hot humid days, you got yourself  a wet location.
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#22
  Re: Underground electrical question by chrisntam (Working on my shed, ...)
When you pull your thwn, pull an extra black wire (I would pull a red one, but no need to buy another color spool, you can dab a drop of red or yellow or blue or.. on the ends to identify it...just not white, grey or green. 
   You may not need it now, but it may be advantageous to have two circuits in your shed in the future. Without installing a sub panel the only code compliant way to do that is a multi-wire branch circuit that shares one neutral.
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