Electric outlet placement on column
#21
I agree with metal conduit surface mounted. Use THHN wire instead of the NM-B inside the conduit. NM-B is fine inside the wall/ceiling, of course. On the first column, you could put the GFCI in a box at the top of the column. Personally, I don't put GFCIs on utility circuits.

I'll have the same issue at my new house excepting the run from the breaker will also be exposed, so it will all be metal conduit. My posts are exposed, so I'll have to figure out how to attach conduit and boxes to a round post.
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#22
MC cable down beside the steel and 2x4 then shallow box with a junction box at the top
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#23
When I built my office in the basement, I boxed a column* asymmetrically so there was room on one side for a receptacle and a data port.  It's centered on the beam above, which is also boxed, just for ascetics reasons.  2x3's in the corners, if memory serves, plus some cross bracing, on 2-by sleepers screwed into the concrete floor.  Nothing is actually attached to the column.

But for a garage, even with a finished column like yours, I'd use either Wiremold surface wiring conduit and boxes, or just EMT and surface boxes.  If using a junction box at the top, I'd put a blank face gfci up there in a raised cover, or even a gfci receptacle up top (you can never have enough receptacles - maybe a shelf on the column for chargers?) so you don't have to go down and back.  You can break off there for the downstream receptacles.  There are box fill issues to be conscious of, too, and 12 gauge uses allowable space faster than 14 gauge.

Of course, you can also just put a gfci receptacle as the first in the downstream chain, with one at the new column too.  They're relatively cheap.

*Of course, what I should have done is reinforce the beam and remove the column, but I got lazy. Might have been the same amount of work, as the column boxing and wiring would have been eliminated, and boxing the beam would have been a little easier.  
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Couldn't find gray data ports and plates.  And pay no attention to the pockmarks in the taping compound surface.  Didn't see that until it was painted. My waste basket hides it.  
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Tom

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#24
I like to isolate GFI's so if one goes toes up I don't have to chase down which one just the one I am looking at.
Phydeaux said "Loving your enemy and doing good for those that hurt you does not preclude killing them if they make that necessary."


Phil Thien

women have trouble understanding Trump's MAGA theme because they had so little involvement in making America great the first time around.

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#25
Cooler Wrote:I had the boxes mounted chest high. I don't see the need to hide them near the floor and it is easier to reach when chest high.
Agreed. I'm putting all the outlets at just over 48" or so.

Phil Thien Wrote:You could also just run Romex right down the column and then cover it with your own removable chase made from pocket-screwed plywood. That would provide ease of access for any changes in the future. Extra points if you conceal the chase by turning it into a holder for any shop items like tape measures, first aid kit, paper towel dispenser, etc.
Haha, that sounds like a challenge! I always like extra points. Although I'm not sure my own custom-built removable chase would make future modifications much easier than the short section of conduit.

Mr_Mike Wrote:I agree with metal conduit surface mounted. Use THHN wire instead of the NM-B inside the conduit. NM-B is fine inside the wall/ceiling, of course. On the first column, you could put the GFCI in a box at the top of the column. Personally, I don't put GFCIs on utility circuits.
I would use THHN, except that doing so would require me to use conduit for the full length of the run, not just the final exposed section. And I don't currently have any THHN, so I'd have to buy three rolls. From my understanding, NM-B is fine in this situation where the conduit is being used just for protection on a relatively short run, not as a fully enclosed conduit "system".

Is there not a restriction about having the GFCI too high? I thought it had to be "accessible". I would otherwise be fine mounting it on the ceiling. Also, I'm not a fan of GFCIs, especially for these garage circuits where I'll have a lot of motors. But since this is part of a much bigger project of installing a 100A sub-panel in the garage, I'm actually going through the trouble of getting it inspected. And thus, GFCIs are required (and tamper resistant). If I were just adding a single circuit, I probably wouldn't bother.

fixtureman Wrote:MC cable down beside the steel and 2x4 then shallow box with a junction box at the top
Behind the drywall? Why MC behind drywall? Just to make the connection to the boxes? I have to imagine that 6AWG MC wire might be a bit tough to snake in that gap between the steel post and 2x4, if it would fit at all.

TDKPE Wrote:But for a garage, even with a finished column like yours, I'd use either Wiremold surface wiring conduit and boxes, or just EMT and surface boxes. If using a junction box at the top, I'd put a blank face gfci up there in a raised cover, or even a gfci receptacle up top (you can never have enough receptacles - maybe a shelf on the column for chargers?) so you don't have to go down and back. You can break off there for the downstream receptacles. There are box fill issues to be conscious of, too, and 12 gauge uses allowable space faster than 14 gauge.

Of course, you can also just put a gfci receptacle as the first in the downstream chain, with one at the new column too. They're relatively cheap.
Similar to before, I'm uncertain about if there's a max height restriction on GFCI receptacles to keep them "accessible". I'll have to try to find info on that. I already mounted a bunch of outlets on the ceiling for lights, using a 2-gang box next to each light, so I'm not too worried about having ample receptacles up there. Although, as you said, more never hurts. And yes, using two GFCIs on this circuit wouldn't be a bad idea.

Bob10 Wrote:I like to isolate GFI's so if one goes toes up I don't have to chase down which one just the one I am looking at.
Certainly makes life easier. But they're also a good bit more expensive than normal outlets, especially given the quantity I'm putting in. I'm trying to lay out my circuits in a fairly logical method so if I trip a GFCI, it's obvious which needs to be reset.

Just as an FYI, I'm putting tons of circuits all over my 2-car garage, as it is my wood shop. Four 20A 120V circuits, four 20A 240V circuits (three of which have wiring to make them 30A capable), and one 30A 240V circuit (with wiring to make it 50A capable). Essentially one of each type of circuit on each wall plus one down the center, with the big 30A/50A circuit just down the center. Plus a circuit on the ceiling for lights, garage door openers, and anything else small.

Thanks,
Tyler
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#26
Remember the 50 amp 240v receptacle needs more space than the other receptacles.  Also you would be hard pressed to enter the back of the box as far as bending radius.    Is that chase at the top used as a air duct, such as a cold air return in it self ?   If so other rules apply as to cables in it.   Roly
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#27
(01-10-2018, 11:44 AM)OneStaple Wrote: Is there not a restriction about having the GFCI too high?  I thought it had to be "accessible".  I would otherwise be fine mounting it on the ceiling.

Quite right.  In fact, it has to be "readily accessible". 

"Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, chairs, and so forth."  (based on Art. 100 'definitions')

That would preclude putting it on the ceiling.  My bad.  
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Tom

“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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#28
(01-10-2018, 11:55 AM)TDKPE Wrote: Quite right.  In fact, it has to be "readily accessible". 

"Accessible, Readily (Readily Accessible). Capable of being reached quickly for operation, renewal, or inspections without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, chairs, and so forth."  (based on Art. 100 'definitions')

That would preclude putting it on the ceiling.  My bad.  
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Hell he could just put in a GFI breaker and no more worries

or isolate just the one breaker on the column
Phydeaux said "Loving your enemy and doing good for those that hurt you does not preclude killing them if they make that necessary."


Phil Thien

women have trouble understanding Trump's MAGA theme because they had so little involvement in making America great the first time around.

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#29
(01-10-2018, 11:58 AM)Bob10 Wrote: Hell he could just put in a GFI breaker and no more worries

or isolate just the one breaker on the column

Either one.  Yup.  Or separate gfci receptacles, one on the column, and the first in the downstream chain.  This, as I understand it, is to eliminate the down-and-back wire run, though it's only a few feet and may not be worth trying to work around.  Extra wire is cheaper than another GFCI, and even 1/2" EMT can handle that with room to spare - 9 conductors with THHN/THWN insulation, in fact, and even with derating based on 7-9 conductors (70% of rated ampacity), that's still 21A, so the 20A circuit ampacity is preserved.
Tom

“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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#30
(01-10-2018, 12:11 PM)TDKPE Wrote: Either one.  Yup.  Or separate gfci receptacles, one on the column, and the first in the downstream chain.  This, as I understand it, is to eliminate the down-and-back wire run, though it's only a few feet and may not be worth trying to work around.  Extra wire is cheaper than another GFCI, and even 1/2" EMT can handle that with room to spare - 9 conductors with THHN/THWN insulation, in fact, and even with derating based on 7-9 conductors (70% of rated ampacity), that's still 21A, so the 20A circuit ampacity is preserved.

I don't know, if it were me I would find the extra $15?  I don't like filling up boxes I might have to revisit so much so all the boxes in my house are at least 4 square.  Not saying a junction box wouldn't have to be opened but far less likely than having to swap out a GFI.
Phydeaux said "Loving your enemy and doing good for those that hurt you does not preclude killing them if they make that necessary."


Phil Thien

women have trouble understanding Trump's MAGA theme because they had so little involvement in making America great the first time around.

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