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Forum topic by Marshall1 posted 11-23-2017 02:35 PM 572 views 0 times favorited 23 replies Add to Favorites Watch
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Marshall1

7 posts in 381 days


11-23-2017 02:35 PM

I am in the process of adding more power to my garage/workshop via a surface mount subpanel. I am planning to run surface mounted 120 and 240 volt outlets, also a 30A 240V electric heater. For ease of installation I wanted to use plastic conduit. Can anyone chime-in on the topic of plastic vs metal conduit?
Also, I wanted to run a 240v outlet for potential use later. I noticed there is 3-wire and 4-wire 240V outlets. Wanted to know which one I should install?


23 replies so far

View Holbs's profile

Holbs

1723 posts in 1867 days


#1 posted 11-23-2017 02:42 PM

At first, I wanted to just simply reply “Really?”
But I am in the construction business so maybe I understand electrical wiring more than if I never been around it.
A big “NO” to plastic conduit for electrical wiring. Plastic conduit is more reserved for “low” voltage applications such as audio/video or voice/data or alarm wires.

-- The Carpenter Bee is derived from the Ancient Greek word wood-cutter

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Sparks500

94 posts in 169 days


#2 posted 11-23-2017 02:45 PM

I don’t know where you’re located so I don’t know the codes in your area. I always keep an eye on the future, as in will I have to change this to sell the building. I like metal, but, I’m an electrician. To me, plastic is for wet areas or underground use where it’s more protected and metal is for everywhere else. Codes in the Chicago area are almost exclusively metal conduit.
Bending conduit is rather easy to learn, but, like I said, it’s basically second nature to me.

-- Rockhound: You realize we're sitting on 45,000 pounds of fuel, one nuclear warhead and a thing that has 270,000 moving parts built by the lowest bidder? Makes you feel good doesn't it?

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becikeja

823 posts in 2651 days


#3 posted 11-23-2017 02:59 PM

Really depends on local code. Most areas of the country you can simply use romex and skip the conduit altogether as long as its covered by the drywall. If you can use plastic conduit you want to make sure you run a separate ground wire. If you use metal conduit, as long as all connections are tight and conductive you can utilize the conduit as your ground. Again, I can’t stress enough to respect your local code. Lets say something does go wrong at some point. If your insurance adjuster determines the circuit was wired non-compliant to local code, you run the risk of a claim not being paid. As mentioned above Chicago mandates metal conduit. My opinion its to protect the local unions which are very strong. In the South they use romex almost exclusively in residential applications, but there are some specific cities with exceptions to this. Bottom line both are safe, but local code dictates the installation. Be cautious, local code can mean state, county and/or city depending on where you live.

-- Don't outsmart your common sense

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WhyMe

910 posts in 1399 days


#4 posted 11-23-2017 03:08 PM

PVC conduit is fine for wiring and is approved by the NEC where installed to code requirements. The down side to PVC it needs more support points to prevent sagging on horizontal runs. EMT is harder to install due to the learning curve of making bends unless you use premade bends and couplers. Just check your local code to see what’s allowed.

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splintergroup

1702 posts in 1060 days


#5 posted 11-23-2017 03:19 PM

Also consider that EMT has a smaller outside diameter than PVC for a given ID and is way easier to feed wire through.

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alittleoff

447 posts in 1115 days


#6 posted 11-23-2017 04:14 PM

Why Me is correct unless you have a local code that says no. AlsoIt will look terrible after a little while. No matter how you install it surface mounted it will sag and will not be level. As for the receptacle just pull another wire for the neutral if the 220 receptacle is 4 wire. Most 220 volt circuits such as saws and motors don’t require a netural.


PVC conduit is fine for wiring and is approved by the NEC where installed to code requirements. The down side to PVC it needs more support points to prevent sagging on horizontal runs. EMT is harder to install due to the learning curve of making bends unless you use premade bends and couplers. Just check your local code to see what s allowed.

- WhyMe


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MrRon

4496 posts in 3082 days


#7 posted 11-23-2017 05:05 PM

If you want to do it right and you are not concerned by a minor increase in cost, use EMT. When confronted by an “OK” way and a “best” way, I will always opt for the best way.

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TheFridge

8324 posts in 1324 days


#8 posted 11-23-2017 05:14 PM

Unless you plan on running your car into it or using it as an anvil, pvc will be just fine.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

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Holbs

1723 posts in 1867 days


#9 posted 11-23-2017 05:57 PM

I guess I stand corrected and admit my error. I thought PVC was a total NONO for inside use of conduit (ok for underground or outside when using outdoor rated electrical cable).

-- The Carpenter Bee is derived from the Ancient Greek word wood-cutter

View richardchaos's profile

richardchaos

578 posts in 218 days


#10 posted 11-23-2017 06:04 PM

I used metal conduit and fitting on my last shop for one they look cool. But when I retrofitted a one car garage insulted and drywalls it I just ran it through the walls and used plastic outlets to save money. It was a pain to get the drywall cut and imp lace and get the outlets coming through the drywall at the exact place. BUT heck thats what tons of plaster are for

-- β€œIn a time of universal deceit, telling the truth is a revolutionary act.” ― George Orwell

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TheFridge

8324 posts in 1324 days


#11 posted 11-23-2017 06:06 PM

No biggie. really you can use it about anywhere. I can’t think of any job off hand that you couldn’t use it for in a residential setting. Not many in a commercial setting as well.

-- Shooting down the walls of heartache. Bang bang. I am. The warrior.

View John_H's profile

John_H

58 posts in 1544 days


#12 posted 11-23-2017 09:13 PM

I think EMT looks better for inside use and it is smaller in diameter

With that being said – PVCis fairly easy to bend just by heating it up with a heat gun so if you have some unusual situations, keep that in mind

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Marshall1

7 posts in 381 days


#13 posted 11-25-2017 01:06 PM

Thanks all for your comments. I appreciate the responses on my first post. I must say to all, I am grateful for the ability to have information on a variety of topics readily available from a wide range of resources. I guess it is the Thanksgiving Thing.
I just returned a bag full of plastic conduit fittings as you persuaded my decision to use metal. The comments about it sagging concerned me as well and the comments regarding the local code. In Dayton OH I believe plastic is acceptable but going with metal. Now I get to buy a tubing bender.

As for my 240m volt question, I have always found this odd not to have a natural when running 240v. I will add a spare ground wire just in case I need one for my short 50A 240V run. May need it for a welder connection.

My Delta TS has an option of running on 120 or 240V. Any advantage to me making the switch? My initial thought was that it would limit my placement of the saw. On the upside, I am sure the motor will run better. Anyone have experience with this?

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MrRon

4496 posts in 3082 days


#14 posted 11-25-2017 07:15 PM

Whether 120 or 240, the saw will run the same; no better, no worse.

View WhyMe's profile

WhyMe

910 posts in 1399 days


#15 posted 11-25-2017 07:41 PM

Actually the motor will run cooler on 240V, less amp draw. Power wise there is no difference, but I do believe running it on 240V vs 120V does help with motor life.

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