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I'm redoing some of the lights on my garage ceiling and was wondering if it was OK to run some Romex in conduit or flex conduit down this support column and attach an outlet. I'm usually working in the center of the garage and hate having to walk over to the wall to plug in my sander, jigsaw, etc. Would use a metal box with 14ga Romex.

Not sure if there is an up-to-code method for attaching something here, but the rest of the garage would probably make an inspector sweat anyway. DIY job from back in the day where they ran Romex underground from the house. There are two circuits for the whole garage and all of the lights and outlets on the first floor area are on one circuit with a 15A breaker. I try and only use one high output tool at once. And I'm replacing all the lights with 11W LED T8 bulbs (about 20, so I think that's about 2A, right?).

Thanks!

Wood Beam Gas Building material Hardwood
 

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Another way which is bulky, but will work, is to get a pipe hanger strap (electrical department) around the pole and attach a smaller strap to it with a bolt and nut. Try a self drilling screw 1st depending on thickness of the pole.
 

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Romex should not be run in conduit

one reason you don't put romex in conduit is because it creates more heat and is not advised in conduit if you have conduit you can run insulated wires instead it's probably cheaper. when you put romex inside conduit The Romex cannot breathe and retains too much heat.
 

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Also, can I use 14/3 in 3/4 conduit? I found a bunch of fill formulas bit was a bit lost. I have lots of Romex but no THHN
For conduit fill purposes, oval cable is treated as a round wire of the wide dimension. With 1 "wire" in conduit, the conduit ID must be 138% of the wire max OD.

I see no reason to run 14/3 unless you plan to put a light switch there, or if the 14/3 is round vs an oval 14/2 and thus smaller. You cannot use 14/3 to run 2 independent circuits down a conduit. You can't merge the neutrals like that! That's a mess!

Not sure if there is an up-to-code method for attaching something here, but the rest of the garage would probably make an inspector sweat anyway.
Who cares about mistakes in the past? Do it correctly going forward. Eventually you'll have other reasons to bring the other stuff up to Code, and then your newer work will fit right in, instead of being more stuff you have to re-do.

The usual reason you have to bring stuff up to Code is you are selling the house and the buyer's inspector red-flagged it. So here's a wild idea. Instead of doing all the work at the 11th hour, for ZERO benefit to you, how about do it early and enjoy the usefulness of it?

There are two circuits for the whole garage and all of the lights and outlets on the first floor area are on one circuit with a 15A breaker.
And you're power-short in the garage.

Also, fun science fact... home buyers are paying a high premium for houses that are already wired with high-amp EV circuits in the garage. They don't even HAVE an EV... just they think they might someday, and so, pre-wired houses are worth a couple grand higher offer to them (since the offer is folded into the mortgage at ~$6 per month per $1000). That's way cheaper to them than hiring an electrician for ???? thousands if the service needs an upgrade. An EV requires a 240V circuit with 3 wires (if socketed, then NEMA 6-20, 6-30 or 6-50. Never install NEMA 10). EVs do not need neutral, but if you install a NEMA 14-50 that will support an RV also.

So all this says to me "subpanel". Now if one is savvy to science, it turns out large aluminum heavy feeder never had a problem, and #2 aluminum is good for 90A. And it's cheap. Subpanels do need to be placed where they will have "working space" kept clear at all times, so entryways, thresholds, that kind of place. Otherwise you're taping black and yellow zerbra stripe on the floor and yelling at everyone who puts anything there, and that's no fun.
 

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First, let me apologize if what I'm writing is above. For some reason, many of the posts are blank on my wonky computer.

A couple of hints, Bcemail:
It's considered "best practice" to strip the outer jacket, making sure some jacket remains where the NM enters the conduit.
Why?
NFPA 70 requires that NM in conduit must have the outer jacket removed or have the ampacity de-rated if the conduit is over 24" long & there are more than 2 current carrying conductors. * Some inspectors require de-rating even if 2 conductors.
Thus, if you're using 14-3 for a switch, remove the jacket or the ampacity must be de-rated. It gets complicated, but #14 NM starts de-rating from 20 amps, although required to be protected at 15 amps.
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The conductors inside must be compliant for use in the conduit you're installing. With modern NM, NMC & NMS, they are. With older NM 1980's & earlier) , they often are not.
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Be sure ream the cut in the EMT and put a proper busing on the top of the EMT.
There are snap-on ones to go directly on the conduit. Also, you can put a box connector and put a bushing for IMC or rigid conduit that is rated the same temperature, or higher, than the NM ( or conductors inside if it's stripped).
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If you don't want to bend an offset for the box, you can buy setscrew offsets for EMT or use Minerllac style clamps that hold the conduit off the post the proper distance to enter the box.
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I've seen MC cable run on basement posts on inspected jobs. that's fast & easy. Personally, I'm not keenont he idea as the MC is subject to physical damage.

Hope This Helps & Enjoy Your Project!
Paul
 

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I like the ceiling-mounted retractable cord reel idea. To mount the cable to the post, I would clamp some 2x lumber (2x6?) to the column with a couple of u-bolts then use cable straps.
 

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First, let me apologize if what I'm writing is above. For some reason, many of the posts are blank on my wonky computer.

A couple of hints, Bcemail:
It's considered "best practice" to strip the outer jacket, making sure some jacket remains where the NM enters the conduit.
Why?
NFPA 70 requires that NM in conduit must have the outer jacket removed or have the ampacity de-rated if the conduit is over 24" long & there are more than 2 current carrying conductors. * Some inspectors require de-rating even if 2 conductors.
Thus, if you're using 14-3 for a switch, remove the jacket or the ampacity must be de-rated. It gets complicated, but #14 NM starts de-rating from 20 amps, although required to be protected at 15 amps.
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The code does not require the sheath to be removed when using NM in a conduit. Removing the sheath removes the listing of the cable assembly. It is not a best practice, but is a violation.

Removing the sheath does not change the ampacity. Ampacity adjustments do not start at 2 conductors.
 

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Removing the jacket removes the listing only when the conductors are not in the conduit. If the conductors are in the conduit, rated for installation in that conduit (MTW, THWN THHN, Etc.) & labeled individually- they are approved in the pipe without the jacket. They will be one of the types that are listed in NFPA 70 310.13(A) at 90-C

I'm an industrial electrician, primarily medium-to-high voltage, so the only NM work I've done is for friends & family. I also worked part time as an inspector in a large city. Lots of my NM work was basement & garage work with NM and conduit drops. In all the jurisdictions I've done these jobs, the inspectors want the jacket removed for NM in conduit, leaving a maximum of 24" in the conduit. Personally, I'd leave just enough to enter the pipe- perhaps 6" on each end.


I saw mentions above of 12-3 & 14-3. So, I put de-rating there in case the poster is using 3 conductor NM cable (3 current carrying & one equipment grounding conductor- 4 conductors total). An example would be 14-3 for a switch and a receptacle outlet. Then de-rating comes into play. I believe I mentioned de-rating starts at 3 current carrying conductors. (The posts above are not displaying well, so I can't see what I wrote.)
<14-3 CORD is 2 current carrying & one equipment grounding. 3 wires total>

One sure way to get approved is to install a properly sized junction box in the joist bay with the branch circuit conductor's MN cable into it. Then run EMT from the junction box to the post's box. Install THHN, THWN, MTW, RHHW, etc inside. Most big box hardware stores sell it by the foot. Using Minerllac type clamps will avoid having to bend offsets if you don't have a bender available.

PS: I like the drill-tap mentioned by Grounded B above. I've done it on concrete filled columns & steel clad CMUs hundreds of thousands of times over the last 49+ years. It's a bit rough on the tap, so lubricate well. You can also drill for & use concrete screws, such as Tapcon brand instead of tapping on a filled column. A RamSet type powder actuated fastener is another option. If you're doing a lot of basement wall furring, it may be worth the investment.

Here are photos of the two conduit termination methods I mentioned & a Minerllac type clamp:
(Remember to ream the cut ends of the pipe so they are not at all sharp.)
 

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