Workshop wiring

[Brogan]

The more I research this subject, the more I discover how complicated it is.

In the UK we have a single voltage and a single outlet/plug type; you just buy your equipment, plug it in, and use it.

Not so here.

The situation is I need to tell the builder now what additional outlets I need them to run now before drywall goes up.
Ideally I'd get 5 x 120V 20A and 5 x 240V 20A/30A but at $150 and $300 each respectively, I need to keep it to the absolute minimum to avoid shelling out $thousands on wiring.

I thought I could get away with 2 x 120V 20A and 1 x 240V 40A (total cost $600) and use the 240V to run two tools simultaneously.
Apparently that's not possible. I would need to have another dedicated 240V 20A/30A outlet, at a cost of another $300.

A secondary issue is I don't know what amps or even the plug type is going to be for the equipment - I haven't bought it yet.
The three Grizzly table saws I'm considering all have different plugs - 6-20, 6-15, L6-30.
Then there's the dust collector which I haven't even started looking at yet.

So should I get a 240V 15A circuit with a 6-15 socket, a 20A circuit with corresponding socket, a 30A circuit, all three or what?

How do you plan the wiring and outlets in advance? Or is it something which can only be done once you've purchased the tools?
What happens when you change tools? Do you have to rewire the shop, change outlets, etc?

As a newcomer to the country it seems extremely user unfriendly and makes things far more complicated than they need to be.

I'm almost at the point where I'm just going to call it quits and contract out the jobs I want doing in the house rather than do them myself.

 

[Brogan]

After much Googling, this is what I was planning to do with the single 240V outlet - the far right outlet in the image.

https://www.walmart.com/ip/Tripp-Li...39-001-2-L6-20P-to-2-L6-20R-Splitter/23140215

 

[ScottM]

I am not electrical expert but I think you can make your own splitter for a whole lot less then $82.00.

 

[Brogan]

That's what I was planning to do originally but based on everything I've read (and been told here in another thread), it's not permitted as the breaker will be 40A and the receptacles on the splitter will be 20A/30A.

 

[Jeremy Scuteri]

You can split a 20A branch circuit into many 15A or 20A circuits since the breaker will adequately protect all the wiring and receptacles. A 20A receptacle on a 40A breaker allows up to 40A to flow through the 20A receptacle. That is not permitted.

The splitter on the far right splits an existing 20A receptacle into Qty=2 20A receptacles.

Note that most 15A receptacles are rated for 20A, so you can put most 15A receptacles on a 20A breaker.


Having the builder pull a single cable for a 60A subpanel should have you setup for all your future needs. It will likely be cheaper than having them run a bunch of separate branch circuits and gives you future flexibility.

 

[Brogan]

Having the builder pull a single cable for a 60A subpanel should have you setup for all your future needs. It will likely be cheaper than having them run a bunch of separate branch circuits and gives you future flexibility.

I asked for a quote last night - waiting to hear back from them.

I figured a surface mounted 100A sub panel would be the best option - that would provide more than enough capacity for multiple 240V and 120V outlets and make it easy to run surface mounted conduit.

 

[ScottM]

I asked for a quote last night - waiting to hear back from them.

I figured a surface mounted 100A sub panel would be the best option - that would provide more than enough capacity for multiple 240V and 120V outlets and make it easy to run surface mounted conduit.

I went with a 100A sub panel. From that I ran three 220v circuits and four 110v circuits. My 110v are all 20amp. My 220v are all 40 amp. Since I did my own wiring, well my BIL did most of it, I used #10 wire throughout.

 

[Jeremy Scuteri]

I figured a surface mounted 100A sub panel would be the best option - that would provide more than enough capacity for multiple 240V and 120V outlets and make it easy to run surface mounted conduit.

:thumbs_up


If that ends up being crazy expensive, you might ask him the cost for a 60A subpanel and see if that is more reasonable.

 

[Brogan]

Thanks guys - I appreciate the help and input.

I'll follow up once I have the quote from the builder.

 

[Lowlander]

:thumbs_up


If that ends up being crazy expensive, you might ask him the cost for a 60A subpanel and see if that is more reasonable.

If the builder is gouging, just hire your own sub after they are gone. A decent electrician and drywaller would be far less than the prices I'm seeing from you. I have pretty much the same setup as Scott, it is more than I'll ever need in the current shop space.

 

[marinosr]

Agree with above comments about running a 60A subpanel. I can imagine no situation where you would need 100A... two table saws running + a dust collector would put you at ~50A. Here's a good article to help you estimate your maximum loads. http://www.woodmagazine.com/woodwor...shop/critical-questions-about-workshop-wiring

Regarding the splitter, 1) you can make a 40A splitter as said above, 2) if you know your tools will draw <20A each, then you can just make a splitter with 20A parts. It won't be up to code, but it's just a non-permanent plug that you can remove whenever you like, and will never be subject to inspection.

 

[Brogan]

A decent electrician and drywaller would be far less than the prices I'm seeing from you.

I assumed that would be the case also, so asked for a few quotes.

The price for 1 x 240V and 1 x 120V surface mounted was $425-$500 and that was without pulling a permit (which costs $75) and they said the price would go up because of it due to the extra time they would have to spend on site, etc.

Which ironically makes the builder's quote cheaper.

 

[Brogan]

Agree with above comments about running a 60A subpanel. I can imagine no situation where you would need 100A.

That's a good point - the simultaneous load would be well below 100A so yes, I could get away with a 60A panel.

It won't be up to code, but it's just a non-permanent plug that you can remove whenever you like, and will never be subject to inspection.

That's what I was planning to do but perhaps the sub panel is the better option.

 

[jlwest]

I went with a 100 amp box because of the flexibility it provides. If you add a HVAC system it adds up. Also some GFI's were required.

 

[Lowlander]

I assumed that would be the case also, so asked for a few quotes.

The price for 1 x 240V and 1 x 120V surface mounted was $425-$500 and that was without pulling a permit (which costs $75) and they said the price would go up because of it due to the extra time they would have to spend on site, etc.

Which ironically makes the builder's quote cheaper.

Good grief! That's expensive.
I would have the builder finish. Pull a permit if needed. Then install the sub breaker, conduit lines, electrical boxes and wires where you want them. Find a decent electrician and have them hook everything up.

 

[redknife]

I assumed that would be the case also, so asked for a few quotes.

The price for 1 x 240V and 1 x 120V surface mounted was $425-$500 and that was without pulling a permit (which costs $75) and they said the price would go up because of it due to the extra time they would have to spend on site, etc.

Which ironically makes the builder's quote cheaper.

I haven't seen those kind of rates for electrical work. I have had a lot of electrical work done and done a lot myself with inspection. Good electricians can do that work in no time at all. The wire does cost more than you'd expect. Maybe look around a bit or get electrical contractor recs from NCWW members in your area. Most all of us have gone through a lot of electric upgrades. Make a thread "need electrician rec for Morrisville, NC".
I wouldn't get too discouraged. It strikes me that the builder issue is creating undue pressure. You can take it or leave it and still be fine. I see one 240 in your immediate future and a couple 120's on separate circuits. You can structure for the final expected capacity (which honestly who knows) or piece-meal it as you acquire equipment. Have you thought of wiring your own? You seem the type that could work that out. There may be a local NCWW member that could give on site advice.
To me, there are two main shop electrical scenarios that come up: new to the field and just acquiring some equipment. Building the electrical capacity for a finished shop doesn't make a lot of sense unless you are dead set that you are going to buy and use a lot of specific equipment. Second common scenario is moving the shop or rebuilding the shop. This is where it makes sense to place outlets every "x" feet, multiple 240's, extensive lighting, etc. That's just my opinion, of course, but I think you are veering in to the latter when you have no big equipment currently at all.
All that said, a subpanel would be nice because you would start with flexibility. Of course you could let them finish and then add a subpanel.
Lots of options here. Power tools need power. About everybody on the forum deals with these issues. Get informed then do what feels best for you and your current budget.

 

[tri4sale]

I assumed that would be the case also, so asked for a few quotes.

The price for 1 x 240V and 1 x 120V surface mounted was $425-$500 and that was without pulling a permit (which costs $75) and they said the price would go up because of it due to the extra time they would have to spend on site, etc.

Which ironically makes the builder's quote cheaper.

Pull the permit yourself, then you don't have to pay the electrician to go to town hall to pull permit, etc. The permit's I've pulled let me specify the licensed contractor doing the work, just because you pull the permit doesn't mean you have to do it yourself.

Remember when you sell your house, you have to disclose if you've done work like this and if you've had a permit. Without a permit you can potentially derail the sale. Had a recent sale the appraiser red flagged some work done without a permit, lender required a permit be pulled before they'd loan.

Prices are up on everything due to shortage of qualified contractors, so they've upped their pricing, supply/demand, blah blah blah. End result is it's more expensive and harder to get contractors to do the work. I've got some small electrical jobs I need done that my normal contractor has basically said he's too busy with large jobs (new construction work) to do the small jobs anymore.

 

[DaveD]

Have the builder put in a 60amp sub panel and then do the rest later in exposed conduit. That way you can calmly plan what you need/want. With a little guidance, wiring isn't a big deal. Homeowners can typically pull their own permits and do their own wiring.

A 100 amp sub panel might be better just from the standpoint it will hold more breakers. Cost will depend a lot on how far the sub is from the main disconnect panel.

What you don't want to do is have all your shop lighting fed from the sub panel. If the main breaker to/in the sub ever trips your lights will also go out if fed from the sub.

 

[Jeff]

I thought I could get away with 2 x 120V 20A and 1 x 240V 40A (total cost $600) and use the 240V to run two tools simultaneously.
Apparently that's not possible. I would need to have another dedicated 240V 20A/30A outlet, at a cost of another $300.

That's penny-wise and pound-foolish! :thumbs_do

I'm an electrical dummy without deep pockets but I'd get a turnkey job done to my specifications from square one and stop agonizing. You're already spending a lot more than a few thousand to build your new home so another +/- $1k is relatively insignificant at the end of the day.

I'm almost at the point where I'm just going to call it quits and contract out the jobs I want doing in the house rather than do them myself.

You're call! What about all of those woodworking heirloom pieces that you'll be crafting to make it a home instead of a house?

 

[KenOfCary]

One note the Grizzly 6-15 plug will fit into a 6-20 socket but not vice versa. If you have both 15 and 20 Amp equipment just install 20 Amp sockets and breakers so they can be used for both types of equipment. 30 Amp equipment usually requires a twist lock socket and plug - like you see on electric dryers.

I'm not an electrician and this information is just based on my observations of what real electricians have installed in my shop, so take it for what it is. Non expert observations, not real advice.