Electrical ceiling drop ideas

[Mark Levitski]

After about 6 years of using more "temporary" (ha!) electric service to various woodshop tools, I am finally installing a more permanent yet flexible system using EMT. The shop is a pole barn with a concrete floor and a metal corrugated ceiling with the typical 8' on center trusses. All has worked out well for the lighting and DC ductwork, both being suspended from the ceiling and both installed much earlier. Also put in earlier with the lighting was in-wall electric outlets, all 110V. Now all I want to do is get some ceiling drops for the bigger equipment, both 110 and 220. I will run the EMT along the ceiling, then come down where I need to to serve things. This will get almost all of the temp wiring off the floor.

My question is how to come down? My idea was to run the EMT right down to the floor and use some construction adhesive on the metal boxes. Another idea was to install a post and follow that down, though more trouble due to the 8' OC trusses (I'd have to get up in the attic and put in some more wood between those to support the top of the post). Then there are restrained drops hanging in mid-air that leave an unprotected wire exposed to whatever is flying around the shop.

The shop is 36 X 40 X 12 with 2-10' overhead doors and one service entrance. Tools are lathe, 6HP bandsaw, 2HP bandsaw, 8" jointer, 20" planer, 5HP dust collector, Wood Wizz (all 220V), 22-44 drum sander, 3 buffing machines and a grinder, 1HP drill press, (all 110V).

Any ideas on how to get down to the floor?

Thanks.............Mark

[Logan William]

What I would recommend is putting boxes on the ceiling above where you want the power drops, then use cord reliefs/cord strain reliefs to hold bus drop cord and use that to come down from your box to the receptacle or plug at the end. Go to McMaster.com and search for cable cord grips or cable strain reliefs then also search for bus drops for the heavy duty bus drop cables. Keeps the cords off the floor, fairly easily to move around when needed and reliable.

[Jim O'Dell]

What I did is similar to what Logan suggests. I have ceiling mounted 110 and 220 volt twist lock receptacles. I used a 12 gauge extension cord and cut the ends off to rewire for the 1 1/2 hp contractor saw, and some 10 gauge cord for the 3 hp cabinet saw. I'm relying on the twist lock to secure the cord, but both run down and are strapped to the 6" PVC pipe that services both saws, so nothing can grab the cords and yank on them. Jim.

[John Lifer]

Not to code, but I ran light cable from ceiling to the metal box with outlets. Takes the load off the electric cord. Used 12g rubber coated cords.
They swing, but just above head height so I can reach to plug in.

[Jamie Buxton]

You've got a big chip collector. That makes me guess there's big ducts near the ceiling, and sizable drops down to each of those stationary machines. Can't you just strap the wiring to the duct drops?

[Doug Palmer]

Bring down EMT conduit from the ceiling is one way to get your circuit down to a usable level, but be sure it is where it will not interfere with your work or with manuevering boards. An alternate is to bring down a cord that is not in conduit like Logan has suggested. You cannot use regular romex for this type of installation, if you want to meet code. You can however install a flexible cable approved for this type of installation. It should be SOOW or SJ cable. The SJ cable is rated at 300volts and is a little cheaper. The SOOW cable is rated for 600 volts, which is overkill, but the insulation is much thicker and resists cutting and damage much better. Install cord grips at the cable ends. Strain reliefs are a good idea at the top, but not required when the proper cord grip is used.

Note: there is nothing wrong with the EMT idea, as long as it does not create an interference issue.