Wiring with 240 VAC / 120 VAC At Every Outlet

[Julie Moriarty]

PS. I'm sure a lot of you are starting to think, "You're over-thinking this project!!!" That's true, but it won't stop raining! The dozer is waiting to lay down the gravel.

When you can't work, think away! Overthinking can save you a lot of work later on.

When in doubt, add a box. When in doubt, leave a loop of wire when pulling. If you pull in two networks, one with (3) #12 and one with (3) #10 and leave loops at every box where drops might be, you should be covered for anything your shop will need. Unless you start buying big commercial machines.

[Van Huskey]

First, I don't want to be a downer but it seems the genesis of the thread is "future-proofing". All I can say is I wish I had all the money I spent on future proofing and never used back. I "future-proofed" the low voltage in out 2nd home 10 years ago. There is over 1,000 feet of Cat 6 with RJ45 outlets EVERYWHERE and maybe 500 feet of RG6 with outlets for 10 TV, I use absolutely none of the Cat 6 and one run of RG6 to the main satellite box and that is it. Everything is wireless now.

More apropos to a shop I am getting ready to start my 5th shop this fall, there is no way I could have come close to future proofing my earlier shops. I would have never put in 40 amp circuits (now I need multiples), I would not have dreamed I needed a separate 3ph supply up to 40 amps and the massive ampacity needed for the RPC (I ain't runnin' no 3ph machines ever).

My suggestion is run a lot of current capacity into a large service panel, then run the conduit and run the wire and circuits you need now. Adding on will be "easy" in the future but you won't tie money and time up into guessing what you may need in the future since my guess is you will most likely be wrong and be adding circuits and pulling wire anyway.

I may be the odd duck but I won't spend money of future-proofing anything now beyond the basic infrastructure (like using conduit) to make future upgrades simple.

[Paul Lawrence]

That wiring plan settles it for me. I might just have to start a workshop post. Mine would probably be #4259 on this forum, but since it will probably take me until Christmas to do it, we might have some cold weather reading material.

Thanks to everyone for the informative and experienced comments. I can't tell you how important this has been to me, since I have been trying to get this shop started for over a decade. There's always something more important to spend the money on --- like kids growing up, doctors and medicines!

Now if it will only stop raining for a week or two ...

[Jason Roehl]

For single phase systems, this is true. For three phase systems, three circuits can share one neutral.

I think this has changed since you retired. I'm currently working with an industrial/commercial electrician (he's in his late 50s), and he told me last week that his boss told him a few years ago that they could no longer share neutrals on 3-phase circuits that aren't on tied breakers. It's kind of annoying, because my whole building is wired that way from 25 years ago, but I can see how with wiring additions over time, it could become a problem as non-electricians do things "the easy way". (I'm a maintenance tech, and I'm guilty of it at times...)

[Jim Becker]

My suggestion is run a lot of current capacity into a large service panel, then run the conduit and run the wire and circuits you need now. Adding on will be "easy" in the future but you won't tie money and time up into guessing what you may need in the future since my guess is you will most likely be wrong and be adding circuits and pulling wire anyway.

I agree with this...have the available supply there and be generous in your conduit or raceway size. That makes for easy changes later WHEN and only when they are needed. Most often, for me at least, any angst with electrical changes are more about the path, rather than the "stuff".

[Rod Sheridan]

I wired my shop with a multi-wire branch circuit.

it's great, only requires one 2 pole breaker, and every 4 inch square box has a duplex 240 and 120 volt receptacle...................Rod.

[Robert Engel]

Julie,

I've dealt with quite a few electricians over the years and have never heard circuits referred to as networks.

I've always associated networks with LAN systems.

Is this a new term or are you talking about something I've missed out on?

Thx.

[Matt Marsh]

Julie,

I've dealt with quite a few electricians over the years and have never heard circuits referred to as networks.

I've always associated networks with LAN systems.

Is this a new term or are you talking about something I've missed out on?

Thx.

It's probably a regional thing Robert. I have heard the term before, but only online. Here in Northern MN/the Midwest, the slang term is "Boat" or "Full Boat".

[Julie Moriarty]

Julie,

I've dealt with quite a few electricians over the years and have never heard circuits referred to as networks.

I've always associated networks with LAN systems.

Is this a new term or are you talking about something I've missed out on?

Thx.

It's probably regional, Robert. We have names for junction boxes, like 8B & 11B, that I learned later on, maybe 50 miles away, they called them octagon or 4-11 square. But if you're ever in the Chicago area and use terms I use here, you'll be talking the local language.

One time a guy from Iowa came to our local to work. When there's a knockout removed from a box, it has to be filled. We call them KO fillers. When the guy from Iowa needed one he asked me, "Y'all have any blunder plugs?" I looked at him and said, blunder plugs!?!?!" That just cracked me up.

[Terry Kelly]

Julie,

I've dealt with quite a few electricians over the years and have never heard circuits referred to as networks.

I've always associated networks with LAN systems.

Is this a new term or are you talking about something I've missed out on?

Thx.

I use that term as well something I was taught as an apprentice.....have worked with several JW’s from around the country and they have used it too.....single phase system 2 hots and a neutral or 3 phase system 3 hots and a neutral are commonly called a network......today it’s still the same but Some don’t share neutrals....I prefer not to.....

[Matt Marsh]

Where multi-wire branch circuits really shine is when you install several circuits in the same conduit. e.g. When using #12 THWN wire with individual branch circuits in the same raceway, you are limited to 4 circuits before you have to up-size to #10s, or drop to a 15 amp breaker (50% de-rate). With multi-wire branch circuits, you can install eight single phase 120 volt circuits, and nine 3-phase 120 volt circuits, and still use 20 amp breakers.