Surface mounted shop wiring

[Jon_E]

I'm beginning to do some planning for electrical layout and wiring in my new shop. At this point all I know for sure is that I will be running all circuits surface-mounted, nothing buried in the walls. More than likely all of my receptacles will be "drops", basically a conduit run down the wall from ceiling level to a location about 50" above the floor.

For those of you who have done surface-mounted wiring, what do you suggest for materials? EMT or PVC conduit? What size? Metal or plastic boxes? I'd like to see some examples of surface-mounted wiring and if you would do things differently or you are happy with your system?

 

[dogdog]

I used EMT for mine...not that much more... dunno besides that they don't sell pvc here.

3/4 and 1/2 EMTs... on 4x4 metal boxes.....

1/2 EMTs fit about 9 #12 stranded wires comfortably I actually just have 3 #12 (Hot Neutral and ground) and 3 #10s (hot hot Neutral) so each conduit is for 1 120V @20A and 1 240V@30A (ground is shared with 120v and also the metal conduit might not be kosher with some other ppl)


http://www.allenelectric.com/referencedata/conduitfill.htm


material wise....
spools of stranded wires different colors.
conduit benders 1/2 3/4
your conduits and materials you estimate base on your needs.

 

[zmotorsports]

I started out building my shop back in 1995 wanting all my wiring behind the sheetrock. I "thought" I had it all planned out, but even with as much planning as I did, I have acquired more equipment than even I would have thought compared to back when I built the shop.

I have many circuits now surface mounted and have used 1/2 and 3/4" EMT with metal boxes.

Mike.

 

[pattenp]

I used EMT for mine...not that much more... dunno besides that they don't sell pvc here.

3/4 and 1/2 EMTs... on 4x4 metal boxes.....

1/2 EMTs fit about 9 #12 stranded wires comfortably I actually just have 3 #12 (Hot Neutral and ground) and 3 #10s (hot hot Neutral) so each conduit is for 1 120V @20A and 1 240V@30A (ground is shared with 120v and also the metal conduit might not be kosher with some other ppl)


http://www.allenelectric.com/referencedata/conduitfill.htm


material wise....
spools of stranded wires different colors.
conduit benders 1/2 3/4
your conduits and materials you estimate base on your needs.

If I'm reading you right the #12 being used as a ground for the 30A circuit is to small. The 30A circuit is to have a #10 ground if the conduit is not being used as ground. You also need to consider derating the conductors when more than 3 current carrying conductors are installed in conduit.


*

 

[Cmreschke]

Ok 9 #12s in 1/2 inch is legal, but imo not comfortable, actually kind of a pain in the ***. Stick with 3/4 as the difference in cost is minimum. Besides it's only 1 bender instead of 2.

With 10s and 12s you can install up to 9 ccc's before you have to derate further.

 

[finn]

PVC is easier to work with for a novice, but you have to run a ground.

I'd recommend 3.4" conduit as it's easier to pull wires.

Use 1/2" for shorter runs, as desired.

I used PVC for thermostat and 120v wiring to the hanging heater, as well as exterior runs.

 

[Jon_E]

So if you're running stranded wire (THHN or equivalent) are you running the conduit all the way from the panel, or are you running NM-B or BX to a junction box? I had the idea that I could run romex to junction boxes at ceiling level and then just go down the wall with vertical drops.

 

[colt340]

I ran mine all with conduit on the surface. It makes it easier to make a change when needed.

 

[mopar440_6]

My 50'x60' shop is lined with steel, so I'm having my electrician run everything surface mount. I believe his quote shows 3/4" and 1" EMT. The plan is to run everything in a few large EMT tubes from the panel up into the attic, make the pulls to each location with Romex, and then drop down the walls and run across in EMT.

 

[Rrumbler]

I would recommend EMT, and steel boxes and plates or covers. Smart to run it on the surface in a shop or garage environment so changes are easy to make. If it was mine, I'd use all 2-1/2 inch deep 5S boxes(4-11/16 x 4-11/16 square) with 1/2, 3/4, and 1/2-3/4 knockouts (MKO), and appropriate industrial covers for whatever device(s) I installed in the box; buy 'em by the case and go for it. But that's just me and my so called **** retentive way of thinking. You can save some nickels by using 4S, and single gang Handy Boxes, but that will involve more complex planning, and if you want to add a device at some future time you might be changing out boxes.

 

[nadogail]

EMT for the industrial look and ease of installation. I use a combination of 1/2 & 3/4 with compression fittings. I do not like the appearance of set screw fittings.

Wiremold for appearance.

 

[Dragfluid]

Yet another vote for EMT. That's what I've been planning to use in my build, if the damn drywall ever gets up! I like the looks of it better over PVC, plus more durable if it happens to get smacked by something. Don't try to pinch pennies with dinky sized boxes.

Along this line, a question for a Sparky. Can the EMT be used for the grounding conductor in any type of run? Is there an amperage limit?

 

[bczygan]

I ran a line horizontally around the garage in grey PVC with matching Carlon boxes. White outlets and covers. Goes good with shiny white walls and red and black cabinets.

Bill

 

[Lootenny]

Garvin makes a 4 X 4 box with raised knockouts on 2 sides that allows it to be surface mounted on pole barn steel, and allow the EMT to run straight across the ribs.



Sent from my iPhone using Tapatalk

 

[Dragfluid]

Looks good, Ink.

 

[teamo]

3/4" EMT with 4" square boxes 2 1/8" deep. I like the deep boxes for extra room for the devices and future upgrades. If you don't like using the conduit bender you can buy standoff clips that allow connections straight into the box knockouts instead of bending the off sets. I prefer to bend the pipe and use the pipe clips that mount the pipe tight to the wall.

 

[homebuilt burner]

In my dad's shop, the bottom 8' is 3/4 plywood painted the same grey as PVC conduit. I ran 3/4" pvc into steel boxes (all 4x4s). I ran all the way around the shop. Then wired each wall's worth of outlets together. The only problem we run into is near the welder if you use the chop saw and the bench grinder together they trip the breaker. It would be nice to have them on separate circuits.

My plan was to run the air line under the electric with a water line under that. I was working a lot of hours and my nephew "did us a favor" and now the airline is by the ceiling and the water line is a foot off the floor. I had planned on having all three runs above bench height.

 

[frugalguido]

I highly recommend wiremold 3000 series for surface mount wiring. Very easily to add outlets or wiring at a later date, in fact I added some additional outlets after some of the machinery was placed. Here some pictures of mine during install;

 

[Norcal]

I highly recommend wiremold 3000 series for surface mount wiring. Very easily to add outlets or wiring at a later date, in fact I added some additional outlets after some of the machinery was placed. Here some pictures of mine during install;

One disadvantage is if you tug on a cord when it's a locking type plug / connector or larger cord the receptacle can be jerked out of the raceway. It does not tolerate abuse well.

 

[Cmreschke]

Drag, yes emt can be used as the ground when installed properly. Eg, fittings tight, eccentric kos, or if in a concentric ko then bonding bushings to continue the path of ground. No cure nt limitation as your pipe is typically sized by conductor size. The bigger the conductor, the bigger the current draw, equals bigger pipe size anyways. The point really is to make sure all of your conduit is continuous.

 

[zmotorsports]

EMT for the industrial look and ease of installation. I use a combination of 1/2 & 3/4 with compression fittings. I do not like the appearance of set screw fittings.

Wiremold for appearance.

Same here, I prefer the appearance of the compression fittings vs. the screw style.

Mike.

 

[frugalguido]

One disadvantage is if you tug on a cord when it's a locking type plug / connector or larger cord the receptacle can be jerked out of the raceway. It does not tolerate abuse well.

The 120v outlets on mine have a screw that lock the outlet holder/frame to the raceway, the only way the outlet could be pulled off is if you pulled the raceway off the wall, same as EMT. The 220v outlet frame screws directly to the wall then the raceway is run into it.

 

[dogdog]

If I'm reading you right the #12 being used as a ground for the 30A circuit is to small. The 30A circuit is to have a #10 ground if the conduit is not being used as ground. You also need to consider derating the conductors when more than 3 current carrying conductors are installed in conduit.


*

yes the EMT conduit is used as part of ground as well, checked with continuity metal box to EMT and sub panel ground points.... though not too sure regarding the NEC about more than 3 current carrying conductors in the same conduit. but thanks I will look into it.

 

[Dragfluid]

Drag, yes emt can be used as the ground when installed properly. Eg, fittings tight, eccentric kos, or if in a concentric ko then bonding bushings to continue the path of ground. No cure nt limitation as your pipe is typically sized by conductor size. The bigger the conductor, the bigger the current draw, equals bigger pipe size anyways. The point really is to make sure all of your conduit is continuous.

Grounding bushings. Got it! Will have to go to the real electric supply house for those, as the big boxes near by don't stock them.

Thanks CM.

 

[Cmreschke]

Bonding bushings are for if your running into concentric kos. If your running 3/4 your probably not entering into a concentric as the box will probably be 3/4 kos. As long as the connector is in direct contact with the main part of the box you won't need them.

 

[Dragfluid]

Bonding bushings are for if your running into concentric kos. If your running 3/4 your probably not entering into a concentric as the box will probably be 3/4 kos. As long as the connector is in direct contact with the main part of the box you won't need them.

Yes, after I wrote that, I looked into it a little more, and it got a little clearer on what you mean. Yes, I was planning on running 3/4.
Thanks!

 

[Jon_E]

Digging up my own thread here.

So I am installing the underground service and panel this afternoon. The walls will be 1/2" OSB, painted white, and the ceiling will be exposed rough-sawn 2x10's, also painted white. I am trying to decide if there is any advantage to running MC armored cable over NM-B in the ceiling joists, for lighting and a few outlets. Any thoughts? I am comfortable with either one, and there is little chance of disturbance or damage.

 

[nadogail]

Another vote for Wiremold. I have some that has been in service since '73 and still going strong.

Wiremold has been around for almost ever.

 

[ford33]

I used 1/2" and 3/4" EMT surface mounted. In some area's where the electrical conduit and compressor airlines crossed, I used metal strut and pipe mounting hardware to keep the two lines at different heights.

 

[sberry]

3/4" EMT with 4" square boxes 2 1/8" deep. I like the deep boxes for extra room for the devices and future upgrades. If you don't like using the conduit bender you can buy standoff clips that allow connections straight into the box knockouts instead of bending the off sets. I prefer to bend the pipe and use the pipe clips that mount the pipe tight to the wall.

This but those Garvin boxes are way super cool. I dont use any 4 11/16 but both depth of 4x4 and a handi box on occasion.

 

[alfredeneuman]

Wiremold has been around for almost ever.

The first Wiremold was patented in 1900. Along with Harvey Hubbell, it was one of the "original" companies

 

[sberry]

You can use some of each. I might put a few things in the walls and a means of raceway for some stuff I thought I might want to add down the line. Make it easy to get at and not throw a lot of just in case stuff in that never really seems to work out all that well.

 

[raddksn]

I highly recommend wiremold 3000 series for surface mount wiring. Very easily to add outlets or wiring at a later date, in fact I added some additional outlets after some of the machinery was placed. Here some pictures of mine during install;

that's some nice work there!!!

 

[Norcal]

that's some nice work there!!!

The green taped grounding conductor is not code compliant, 6 AWG & smaller must have green colored insulation, tape is not OK.

 

[PoorOwner]

What's the rating and number of conductors allowed in the Wiremold 3000?
Doesn't look like you can buy it from big box store either