Introduction and shop wiring Q

[Randall J Cox]

New forum guy here :) (USAF ret. among 20+ years of other various jobs - now fully ret. and playing in woodshop!). My Q revolves around being able, code-wise, to wire up three 240v outlets to one double pole 240v 50 amp breaker in my shop sub panel. I have two outlets wired up to it now (not in series), Delta 3HP/15 amp planer on one and 3HP Delta Unisaw on the other. Just bought a 1.75HP dust collector and want to run it off 240v at 7.5 amps. Can I just wire up a new outlet to the same breaker? That would be one 50 amp breaker feeding three outlets, is that safe and "legal". Pretty sure the first two are using 10 gauge wire as its really, really stiff stuff. I'd use same on proposed 3 outlet. Worst case is the planer and DC running at same time with combined running amps at 22.5. This is a one man hobby shop, not any kind of production facility... Any advice appreciated. Thanks. Randy

[Wade Lippman]

You need 6 gauge for 50a.
In principle you could do it as long as all your components were rated for 50a; but it wouldn't be particularly safe because the tool wiring isn't rated for 50a.
(people will tell you the breaker is to protect the house wiring and not the tool, and that is true legally, but doesn't make it safe.)
I would reduce the breaker to 30a and run #10 and 30a outlets all around.
A better solution would be to run the DC on one 20a circuit and the other two tools on a second 20a circuit.

[Ben Rivel]

As I understood it you arent running to code as its wired now since you said you are using 10 AWG and for a 50A circuit 6 AWG is required. I would first try to confirm what gauge wire the current wiring is. If it is actuallyl 6 AWG then sure, you could use some more 6 AWG wired in parallel to add another outlet. Or do as Wade suggested downgrade the breaker to a 30A and run 10 AWG to the new outlet. Or run a dedicated 20A using 12 AWG. Thats how I did it in my shop. Two dedicated 220V 20A circuits, one dedicated for the dust collector and one for the tools. Since more than one tool will never be one at the same time there is no issue with the circuit being only a 20A due to non of the tools having more than a 15A current draw.

[Marty Tippin]

Welcome to the Creek. You've jumped right into the deep end with your first post!

Did you install the 50A breaker and wiring that is currently in place, or did some previous owner do that? Either way, you're nowhere near being in compliance with current codes. The wiring and breaker have to be compatible - typically, 12 gauge for a 20A breaker, 10 gauge for a 30A breaker and so on (with *lots* of exceptions - for example, you can use bigger wire on a smaller breaker.) You've got small wire (if it was 6 gauge as required for a 50A breaker, it would almost certainly be stranded, not solid, and likely would only fit into "dryer" type outlets) on a big breaker. The problem you have is that the smaller wire could overheat and catch fire long before the 50A breaker ever trips - the breaker is for protecting the wiring in the wall, not so much the device connected to the wiring.

So, as others have recommended, you'd be better off starting over and running a pair of circuits, one dedicated to the dust collector and another for your tools. And if you're starting from scratch, my advice would be to run 10 gauge wire and a 30A breaker for any and all 220V circuits, as that will give you upward capacity for later use (such as when you decide that you need a 5hp belt sander).

[Mike Heidrick]

Like Marty I would change the existing circuit to a 30amp breaker, and wire in the additional outlets for the ww tools that are needed in series and install a new circuit for the DC.

Just me but I would do 10ga and 30amp for the dc circuit too.

[Randall J Cox]

Welcome to the Creek. You've jumped right into the deep end with your first post!

Did you install the 50A breaker and wiring that is currently in place, or did some previous owner do that? Either way, you're nowhere near being in compliance with current codes. The wiring and breaker have to be compatible - typically, 12 gauge for a 20A breaker, 10 gauge for a 30A breaker and so on (with *lots* of exceptions - for example, you can use bigger wire on a smaller breaker.) You've got small wire (if it was 6 gauge as required for a 50A breaker, it would almost certainly be stranded, not solid, and likely would only fit into "dryer" type outlets) on a big breaker. The problem you have is that the smaller wire could overheat and catch fire long before the 50A breaker ever trips - the breaker is for protecting the wiring in the wall, not so much the device connected to the wiring.

So, as others have recommended, you'd be better off starting over and running a pair of circuits, one dedicated to the dust collector and another for your tools. And if you're starting from scratch, my advice would be to run 10 gauge wire and a 30A breaker for any and all 220V circuits, as that will give you upward capacity for later use (such as when you decide that you need a 5hp belt sander).

Marty - I did not personally install it but, I did have it done by a licensed general contractor when I had my shop expanded a little in 2002. Been running my table saw off that 50 amp circuit since. Guess it's time to get an electrician in to install a bigger panel as I'm out of room to add more breakers. In fact have 8 slimline 20 amp 120v breakers in there also now. I'm more concerned about being safe than "legal", but by getting in code, that resolves the safety issue. Guess I should have asked this Q years ago. Appreciate the comments from all of you, guess I need to spend some more $ to get things straight.... Great forum!! Randy

[Ben Rivel]

What size is the motor in your table saw? Do you even need 50 amps?! My guess is you could remove that 50 amp all together and replace it with a couple of smaller 20 amp breakers and use 12 AWG to your outlets. If you dont have any tools drawing more than say 17 amps and you only have one on at a time per circuit then you dont need anything more than 20 amp circuits. That would free up the room in your panel and would be much cheaper as the outlets, romex and breakers are all a lot less for 20 amp stuff.

[Chris Padilla]

I sense some confusion on what you really have there, Randy. Posting some pictures of what you have there would help us to help you A LOT! :)

Welcome to the forum!

[Randall J Cox]

What size is the motor in your table saw? Do you even need 50 amps?! My guess is you could remove that 50 amp all together and replace it with a couple of smaller 20 amp breakers and use 12 AWG to your outlets. If you dont have any tools drawing more than say 17 amps and you only have one on at a time per circuit then you dont need anything more than 20 amp circuits. That would free up the room in your panel and would be much cheaper as the outlets, romex and breakers are all a lot less for 20 amp stuff.

Ben - I just crawled under the 3hp table saw with light and mirror, motor says 13.7 amps. Replacing the double pole 50 amp breaker with two others is a good idea. Looks like I only have room for two. I could use a dedicated 20 amp for the DC as it will run a lot with one other 240v tool running. Then I could run two parallel outlets off one 30 amp breaker. Does code allow that? I would certainly not be running more than two 240v machines at once. (tablesaw, planer and DC are my only 240v machines with no more planned) Randy

[Randall J Cox]

I sense some confusion on what you really have there, Randy. Posting some pictures of what you have there would help us to help you A LOT! :)

Welcome to the forum! Will do as soon as I find out how to do that...

[Ben Rivel]

Ben - I just crawled under the 3hp table saw with light and mirror, motor says 13.7 amps. Replacing the double pole 50 amp breaker with two others is a good idea. Looks like I only have room for two. I could use a dedicated 20 amp for the DC as it will run a lot with one other 240v tool running. Then I could run two parallel outlets off one 30 amp breaker. Does code allow that? I would certainly not be running more than two 240v machines at once. (tablesaw, planer and DC are my only 240v machines with no more planned) Randy
Sure you can have multiple outlets off one breaker, thats how all your 110V outlets in your house are. We have several in one room or multiple rooms all on the same breaker. You could certainly have two or three outlets coming off that 30A breaker using 10 awg wire for your tools and one 20A breaker dedicated to your dust collector using 12 awg wire.

[Julie Moriarty]

Randy, I cannot ever remember having to install several receptacles off a 50A 2P breaker but I do know when it comes time for inspection, the inspector wants to see the receptacles rated the same as the breaker. Of course, the wire needs to be rated the same, too.

You mentioned you are running out of breaker space in your main panel. You could use that 50A breaker to feed a small sub-panel off which you can feed your 240V machines. You could then install the appropriate breaker (as in satisfies both code and the manufacturer specs) and the appropriate wiring and device for each machine.

[Jim Becker]

Welcome to the 'Creek!!

As noted, it's not the best idea to have a 50 amp 240v breaker on wiring that's not rated to handle 50 amps. If you're using 12g wiring and receptacles with 20 amp ratings, that's what you should have your breaker designated as, for example. It may or may not be the best idea to have more than one 240v receptacle on the same circuit, although many of us have done that for shop flexibility. Where I have more than one 240v receptacle on the same circuit in my shop, there's still only one machine plugged in...I did that so I could move certain defined things around if necessary. Best practice is one circuit per 240v machine especially if more than one needs to run simultaneously.

Now if you have a 50 amp circuit with appropriate wiring for 50 amps and a 50 amp receptacle, you can plug a machine requiring only 20 amps into it (with the appropriate plug to match the receptacle) with no problem. But the "circuit" has to match fully out to that receptacle.

[Wade Lippman]

And in general, it's somewhat frowned upon to have more than one receptacle on the same circuit.

Huh? Better shop for some huge panels if you only have one receptacle per circuit.

[Wade Lippman]

Replacing the double pole 50 amp breaker with two others is a good idea.

You know you can only replace the DP 50a breaker with one DP 20a breaker....
(well, there are duplex breakers, but I don't think we are talking about those)

[Randall J Cox]

You know you can only replace the DP 50a breaker with one DP 20a breaker....
(well, there are duplex breakers, but I don't think we are talking about those)

If I take out the existing two-inch-wide double pole 50 amp, can't I just replace it with a 20 amp and a 30 amp, that are each one inch wide? Then I would run my DC off the dedicated 20 amp circuit (it pulls 7.5 amps) and wire the other two circuits (planer takes 15 and table saw takes 13.7) into the 30 amp - all with the appropriate sized wire of course. Planer and table saw would never be running at same time. Won't that work?

[Don Michaud]

If I take out the existing two-inch-wide double pole 50 amp, can't I just replace it with a 20 amp and a 30 amp, that are each one inch wide? Then I would run my DC off the dedicated 20 amp circuit (it pulls 7.5 amps) and wire the other two circuits (planer takes 15 and table saw takes 13.7) into the 30 amp - all with the appropriate sized wire of course. Planer and table saw would never be running at same time. Won't that work?

Yes, but they won't be 1 inch wide each. Those are called "tandem" and are fed from the same leg. What you need for 2 pole stack breakers are called "quad" breakers. They are technically 1 inch wide each, however the come tied together, designed to feed from both the A and B leg. The 4 poles will be tied, the 2 inner handles will be one double pole and the outer handles will be the other. Eaton/Cutler Hammer is a BQ220230... Sorry I don't have Siemens, GE, or Square D memorized. You will have to look them up depending on what brand load-center you have. Do yourself a favor and get the same brand breakers. Some brands will interchange, but they never seem to fit quite right.

[Randall J Cox]

Looks like exactly what I need. Never knew there was such a breaker. Thanks for info. Great site!! Got some more homework to do but, at least pointed in the right direction now with your advice and that of the others on this thread. Randy

[Randall J Cox]

Don - The below, from the Lowes website, fits your description and looks like what I need - am I right? I have a Homeline 100 amp sub panel which is made by Square D. What I don't understand is that currently I have a 50amp 220v breaker along with 8 20amp 120v (slimline) breakers in there now. Is the subpanel overloaded? How do you determine if overloaded? Can't just add 220 and 120 total amps together can you? By the way, I have added none of the breakers, all done by electricians or general contractors over time.

Homeline 30-Amp 2-Pole Quad Circuit Breaker


The Square D by Schneider Electric Homeline Quad-Pole Tandem Circuit Breaker consists of (2) single-pole, 20 Amp and (1) double-pole, 30 Amp breakers
Requiring only 2 pole spaces, it is used for overload and short-circuit protection of your electrical system
Plug-on design, easy to install
Compatible with Homeline load centers and CSED devices
120/240 Vac
10,000 AIR
ANSI certified and UL listed
Limited lifetime warranty

[Von Bickley]

First I would like to welcome you to The Creek.

From everything that I gather from this post, I would strongly suggest that you get a good electrician. Retired Electrician....

[Marty Tippin]

Based on the kind of questions you're asking, I really think you might be better off hiring an electrician to take care of this for you.

Watch what he (or she!) is doing, ask a lot of questions and then maybe read a book or two on basic home wiring before you try to tackle something like this yourself. Electrical work is not difficult, but a lack of understanding on your part could result in an unsafe situation - either while doing the work or afterward.

[Art Mann]

I don't mean to be too critical, but I agree with Von and Marty. At the very least, you need to buy a book on AC house wiring and study it carefully. The nature of the questions you are asking indicates you might very well install wiring or make modifications that are dangerous.

[Randall J Cox]

I take it all as constructive criticism, no problem. As a matter of fact I did just buy a book on home wiring and read the whole thing. But it didn't seem to go to deep into things, especially 220. That's why I started posted asking questions. I have no problem hiring an electrician to do things, I'm just curious by nature and when I don't know about something I ask questions. I like to learn. I have been reading other web sites on electrical stuff and wikipedia on single and double pole, etc. I'm also kinda cautious by nature, especially with electricity. I at least know that I don't know... So, by my last post is my panel already overloaded by licensed electricians? (I have done no work in that panel.) Thanks. Randy

[Wade Lippman]

Don - The below, from the Lowes website, fits your description and looks like what I need - am I right? I have a Homeline 100 amp sub panel which is made by Square D. What I don't understand is that currently I have a 50amp 220v breaker along with 8 20amp 120v (slimline) breakers in there now. Is the subpanel overloaded? How do you determine if overloaded? Can't just add 220 and 120 total amps together can you? By the way, I have added none of the breakers, all done by electricians or general contractors over time.

Homeline 30-Amp 2-Pole Quad Circuit Breaker


The Square D by Schneider Electric Homeline Quad-Pole Tandem Circuit Breaker consists of (2) single-pole, 20 Amp and (1) double-pole, 30 Amp breakers
Requiring only 2 pole spaces, it is used for overload and short-circuit protection of your electrical system
Plug-on design, easy to install
Compatible with Homeline load centers and CSED devices
120/240 Vac
10,000 AIR
ANSI certified and UL listed
Limited lifetime warranty


That is close to a solution. You could use that to replace your 50a DP breaker and two SP 20a breakers. You could then put a DP 20a breaker in the open space. They make breakers that combine two DPs, but perhaps not for your panel.

The issue of whether your panel will be overloaded is probably beyond the scope of this forum. But if it wasn't overloaded with a 50a load on it (and we don't know that) it probably isn't overloaded with the new stuff.

What was the 50a breaker for? I don't think you ever said.

[Malcolm McLeod]

Homeline 30-Amp 2-Pole Quad Circuit Breaker


The Square D by Schneider Electric Homeline Quad-Pole Tandem Circuit Breaker consists of (2) single-pole, 20 Amp and (1) double-pole, 30 Amp breakers
Requiring only 2 pole spaces, ....



Randy, as I hope you've realized, one hazard of the web is getting info that is less accurate than what you already know. Be careful.

I will try not to compound that except to point out that I believe the breaker above is ALMOST what you need. Do not use (2) single-pole contacts to supply 220Vac. If I understand what you want to accomplish (2ea. 220Vac circuits from existing 'double' space in your panel), then you need a breaker with 2ea. double-pole contacts. Homeline offers one with the outer (double) poles mechanically linked by a goofy looking plate that straddles the inner double poles. Be careful.

And, welcome!! Be careful.

[Randall J Cox]

I sense some confusion on what you really have there, Randy. Posting some pictures of what you have there would help us to help you A LOT! :)

Welcome to the forum!

Sorry for the confusion. Let me try and simplify this. Here's a pic of sub panel in my small shop. All the 8 each 20 amp 120v slimline circuits on the right are taken and being used - 6 of them have nothing to do with my shop. I currently have 2 outlets wired from the 50 amp 220 breaker on the left. I want to add another 220v outlet, 20 amp would be sufficient as it will be for my 1.75HP DC (7.5 amps at 220). I want to go from 2each 220v outlets to 3each 220v outlets from the two-position 50 amp breaker on the left. Hope this helps. Randy

[Julie Moriarty]

Randy, another retired electrician here...

I'm not a fan of mini-breakers. Where I come from, they are illegal in most municipalities. And they invite problems when homeowners try to solve breaker space issues.

As has been mentioned earlier, the information you have provided shows this may be over your head, no matter how many books you have read. I can see there are other possible factors at work that shouldn't be solved online. If everything existing has been installed by an electrician, why try to do this one yourself? If you choose to proceed without calling in a qualified electrician, do yourself a favor and go to Mike Holt's website and take this up there. Most all there are electricians. But you will probably get the same suggestion to call in a pro.

[Robert Engel]

Randall,

You can check with an electrician, but I have 4 - 240V outlets on one 20A circuit to 4 machines.

Code and what works are often two different things.

I would call in an electrician familiar with wiring equipment.

[Randall J Cox]

Will call an electrician and watch and ask questions. Thanks for all your help and insight. Randy

[Marty Tippin]

Sorry for the confusion. Let me try and simplify this. Here's a pic of sub panel in my small shop. All the 8 each 20 amp 120v slimline circuits on the right are taken and being used - 6 of them have nothing to do with my shop. I currently have 2 outlets wired from the 50 amp 220 breaker on the left. I want to add another 220v outlet, 20 amp would be sufficient as it will be for my 1.75HP DC (7.5 amps at 220). I want to go from 2each 220v outlets to 3each 220v outlets from the two-position 50 amp breaker on the left. Hope this helps. Randy

The first thing that jumps out at me from your photo is that you've got two wires in each terminal of the 50A breaker - that's a big no-no; you can have only one wire on each terminal of a circuit breaker. The solution is to connect the two circuits plus a short pigtail in a junction box outside the breaker box and bring the pigtail into the box.

From your statement above, it sounds like you just want to add an additional outlet (not an additional *circuit*) - if that's the case, you don't need to (and shouldn't) run wire all the way to the breaker for that - just find the existing 220v outlet that's closest to where you want the new outlet to be and run wire from the existing outlet to the new one. If you really want to run wire back to (or near to) the breaker box, that external junction box you're going to install to resolve the issue with the existing wiring on the 50A breaker would be a good place to attach the third wiring run for the new outlet. But again, all you really need to do is daisy-chain from the nearest outlet that already exists (via an in-the-box pigtail, if necessary) to the new outlet.

If you don't do anything else, you should at least replace that 50a breaker with one that is appropriate for the wire size that runs to the breaker today -- if it's 10ga wire, use a 30a breaker; if it's 12ga wire, use a 20a breaker. It's heard to tell from the photo, but the wire going to the 50A breaker doesn't look any bigger than the rest of the wire in the box. You'd need to find a section of that wire that still has the insulation jacket on it to read what it says.

There may be other issues with the wiring in your sub-panel (I'm concerned that the ground and neutral aren't separated, but that my not apply to your situation). The recommendation to get a professional electrician (not a home contractor) to come look at it and help you resolve the issues still stands.

Good luck - let us know how it turns out!

[Art Mann]

I agree completely with Marty. It appears that what the person who wired that box did was bring in the two yellow cables with (probably) 10AWG wire to create the 50A capacity. That is strictly forbidden in the National or any local codes of which I am aware. There is another problem too. The neutral and ground wires are "bonded" or tied together electrically. This should only be done in one location in the main breaker box. It should never be done in a sub panel. It precludes the correct installation of 120VAC circuits because there is no separate neutral wire. These issues create potentially dangerous conditions that no professional electrician would ever install and no electrical inspector would ever approve. I am glad you posted the photo even though it didn't bring good news. You need to know these things.

[Chris Padilla]

The first thing that jumps out at me from your photo is that you've got two wires in each terminal of the 50A breaker - that's a big no-no; you can have only one wire on each terminal of a circuit breaker. The solution is to connect the two circuits plus a short pigtail in a junction box outside the breaker box and bring the pigtail into the box.

I think it may be up to the AHJ (authority having jurisdiction) but wire splices can be in a breaker box as long as it is neat and fill requirements of the box are not exceeded and one end of the splice terminates in a breaker (i.e. not a pass-through connection)...as my AHJ explained to me. I do agree with double-tap wire in a breaker...they are designed to handle one but usually this can be easily and quickly remedied with a wire-nutted splice.

Randy, as you can see, NEC is a guide but the local AHJs are the ones who will sign (or not sign) off on your work as the rules are interpreted by them! What flies in a home may not fly in a work building and vice versa. Some municipalities go by 2011 NEC and some use the newer 2013...some may still like 2008. It is kinda crazy. Pay to have a pro help you and educate you about the local codes such that in the future, you might be able to handle things on your own. Good Luck...we're always here as a sounding board and opinions are aplenty! :)

Oh and if that is truly a SUB-panel (coming off the MAIN panel of your home), then that is HUGE no-no having the white neutral and bare ground wires bonded/shorted together. They need to be isolated from each other. This is true for all SUB panels. Only the MAIN has them bonded together. This is purely for safety reasons in how the ground works to shut circuits down in case a hot wire touches a metal case or enclosure of some kind. I'll be the third guy to point this violation out.

[Art Mann]

Chris, I don't mean to be argumentative, but I don't believe there has been a NFPA NEC code released in the last 20 years that would permit feeding a sub panel with two separate wires that are tied together at the breaker on either end. If there are local codes that will permit it, the people who developed it don't understand electrical safety. Please check your sources. Suppose one of the two wires comes loose or is cut at some place between the panel and the sub panel. In a fault condition, you could have a situation in which a 10AWG wire is conducting 50A continuously or 100A for a minute or so. That is just asking for a fire.

[Chris Padilla]

I did not say that, Art, or perhaps I was unclear. You cannot put two wires (hots) into a breaker. I think we agree on that. You can, at least here, splice/wire-nut two wires (hots) together with a short wire coming out and put THAT into the breaker. That is all I was saying. This can all be done IN the breaker box. There is no reason to move outside the breaker box into some junction box, splice, then go back into the breaker box.

[Wade Lippman]

I did not say that, Art, or perhaps I was unclear. You cannot put two wires (hots) into a breaker. I think we agree on that. You can, at least here, splice/wire-nut two wires (hots) together with a short wire coming out and put THAT into the breaker. That is all I was saying. This can all be done IN the breaker box. There is no reason to move outside the breaker box into some junction box, splice, then go back into the breaker box.

If the breaker is rated for two wires then you can put two wires in it. Otherwise one wire.
I don't remember what make it was, but I had a house with breakers rated for two wires. There were two slots in the clamps. In general though having two circuits on one breaker is bad practice. I had a house with 3 20a circuits pigtailed going to one 50a breaker; that is potentially tragic practice, but I suspect it is what the OP is doing. He has never explained what his 50a breaker is for.

[Art Mann]

I just took a second look at the sub panel and there is no protection on the feed. I misinterpreted what was going on.

[Jim Becker]

Huh? Better shop for some huge panels if you only have one receptacle per circuit.
I was referring to 240v receptacles. Sorry I wasn't clear on that...my bad...I've clarified it in my original post. Thanks!

[Randall J Cox]

If the breaker is rated for two wires then you can put two wires in it. Otherwise one wire.
I don't remember what make it was, but I had a house with breakers rated for two wires. There were two slots in the clamps. In general though having two circuits on one breaker is bad practice. I had a house with 3 20a circuits pigtailed going to one 50a breaker; that is potentially tragic practice, but I suspect it is what the OP is doing. He has never explained what his 50a breaker is for.

Wade - The 50 amp breaker is used with two separate wire feeds of 10 gauge wire, one powering a 220v 15 amp 15" planer and the other to my 220v 13.7 amp table saw (at least the wiring going to these is 10 gauge). Now that I have done some studying and reading and with the comments here, I see lots of problems in my panel. I should replace the 50 amp breaker with a 30 and a 20. The 30 powering my table saw and DC (1.75hp 220v 7.5 amps) on one circuit with two outlets. The 20 amp dedicated for the planer. I also see I "probably" shouldn't have two wires going to the 50 amp breaker, but that will be fixed with that breaker replaced. I also see the folks who wired the panel combined the common and bare wires on one bar instead of adding a bonding (I think the term is) bar connected by a bare wire back to the main breaker. i also found one 120v 20 amp breaker using 14 gauge wire. (And maybe there are more problems.) If I hadn't started this discussion asking some dumb questions, I never would have found all this. I truly appreciate all the comments. Hopefully I get it fixed before I burn the house down. Randy

[roger wiegand]

I was referring to 240v receptacles. Sorry I wasn't clear on that...my bad...I've clarified it in my original post. Thanks!

Jim-- I'm still not sure where you're getting this. I've done many permitted and inspected projects where the electricians have run multiple 240 and 120V receptacles on MWBCs, have run strings of 208 V receptacles on three phase circuits, and in my own shop, multiple 240V outlets on a two-wire (plus ground) single phase circuit. Neither the electricians, architects, nor inspectors have so much as blinked at any of this. If you have multiple low-draw loads or things that will never be turned on at the same time it wouldn't make any sense to have to put each on it's own circuit. A big saw, an electric heater, or a compressor, sure.

[Chris Padilla]

If I hadn't started this discussion asking some dumb questions, I never would have found all this. I truly appreciate all the comments. Hopefully I get it fixed before I burn the house down. Randy

And if I hadn't requested a picture.... ;) There are a lot of problems...unsafe problems...with that sub-panel, Randy. Shut down the breaker to it and start fixin' it!

Edit:

I just got to looking more closely at the picture. Am I right in that the feed INto the sub-panel is done with 2 conductors plus ground? I don't see a red wire or a third conductor. So this must mean the whole sub-panel is 240 V only? With no neutral, there is no 120 V, right? One can 'cheat' and use the ground as the split to get 120 V, however, but that is wrong, wrong, wrong and very dangerous...which is what appears was done here. So all the bare wires will have constantly-flowing current on them when that circuit is in use as well as the feeder ground constantly flowing current. This means the actual metal box is likely energized since all that bare copper is likely touching it! Shut this box down pronto and then step back and assess things, Randy. I hope I am wrong here and I'm missing something but that is what it looks like to me.

[Jeff Keith]

Jim-- I'm still not sure where you're getting this. I've done many permitted and inspected projects where the electricians have run multiple 240 and 120V receptacles on MWBCs, have run strings of 208 V receptacles on three phase circuits, and in my own shop, multiple 240V outlets on a two-wire (plus ground) single phase circuit. Neither the electricians, architects, nor inspectors have so much as blinked at any of this. If you have multiple low-draw loads or things that will never be turned on at the same time it wouldn't make any sense to have to put each on it's own circuit. A big saw, an electric heater, or a compressor, sure.
That was my understanding as well. I'm planning out the wiring for my shop, and I really hope I don't need to run separate 240v circuits for each receptacle.

[Chris Padilla]

Jeff,

I don't think there is any rule against daisy-chaining 240V circuits however by the time you need the high current of these guys, going with dedicated breakers per outlet may not be a bad idea. After all, MOST of the 15 and 20 A 120V circuits in a typical house ARE daisy-chained but then again MOST of the items plugged into those circuits don't have heavy draws. Just look at the items in a typical house that get dedicated circuits: dryer and stove and a/c and electric water heater are probably the top ones. Now look at your garage/shop and decide what really needs a dedicated circuit. In other words, what could be running simultaneously? In my mind, you could be running your table saw with the dust collection running (big cyclone perhaps) and the compressor suddenly kicks on. Further, you could be doing this in the winter time and have the electric heater going as well. It is just something to chew on. Frankly, I found it easier to simply run all my 240V/30A outlets with dedicated breakers. Then you have no worries where you need to plug in or need to remember which outlets are daisy-chained. Believe me, as you get older, you forget how you did something 10 years ago!! LOL!

And if you really want to future-proof your outlets, run 10/2 or 10/3 to everything and then you can make it whatever you want and likely cover 99% of your needs except for that welder you suddenly 'need' and you'll have to run a 50A circuit for that one. :)

[Jeff Keith]

Frankly, I found it easier to simply run all my 240V/30A outlets with dedicated breakers. Then you have no worries where you need to plug in or need to remember which outlets are daisy-chained. Believe me, as you get older, you forget how you did something 10 years ago!! LOL!
Good point. I had forgotten about that age thingy. ;)

My dust collection is mobile, so I'd like to have more than one spot on the wall to plug that in. My other 240v machines are not as mobile and dedicated breakers makes sense.

[Randall J Cox]

And if I hadn't requested a picture.... ;) There are a lot of problems...unsafe problems...with that sub-panel, Randy. Shut down the breaker to it and start fixin' it!

Edit:

I just got to looking more closely at the picture. Am I right in that the feed INto the sub-panel is done with 2 conductors plus ground? I don't see a red wire or a third conductor. So this must mean the whole sub-panel is 240 V only? With no neutral, there is no 120 V, right? One can 'cheat' and use the ground as the split to get 120 V, however, but that is wrong, wrong, wrong and very dangerous...which is what appears was done here. So all the bare wires will have constantly-flowing current on them when that circuit is in use as well as the feeder ground constantly flowing current. This means the actual metal box is likely energized since all that bare copper is likely touching it! Shut this box down pronto and then step back and assess things, Randy. I hope I am wrong here and I'm missing something but that is what it looks like to me.

Chris, you are absolutely correct. I went out and looked very carefully without touching anything (ha ha) and there are only three wires coming in on the feed. A black, a white and a bare copper ground wire. Damn, another problem to fix (not by me, too many issues in this panel). Interesting that its been this way for the past 12 or so years. I need find an electrician and have it all corrected. So glad I posted a pic!!! Thanks Chris!

[Jim Becker]

Jim-- I'm still not sure where you're getting this. I've done many permitted and inspected projects where the electricians have run multiple 240 and 120V receptacles on MWBCs, have run strings of 208 V receptacles on three phase circuits, and in my own shop, multiple 240V outlets on a two-wire (plus ground) single phase circuit. Neither the electricians, architects, nor inspectors have so much as blinked at any of this. If you have multiple low-draw loads or things that will never be turned on at the same time it wouldn't make any sense to have to put each on it's own circuit. A big saw, an electric heater, or a compressor, sure.
I do understand that you can do this and there's no rule against it. (other than for certain types of specific loads) It even makes sense for convenience as you point out and to accommodate a smaller panel for a one-person shop. I just don't prefer it as a "best practice" where there's even remotely a chance that two things might get turned on at the same time. In my shop, it's been easier to run dedicated because I have a full size load center and it's centrally located, more or less, in the space, so that's likely encouraged my opinion, too.

One thing, however, I find it's best to split the circuit in a "generously sized" j-box, rather than trying to "daisy chain" and cram the heavier wire and larger recepticle into the wall box. More than one licensed electrician suggested that to me when I was building out my shop. Some may disagree with that, too...

[Dan Hahr]

Wade - The 50 amp breaker is used with two separate wire feeds of 10 gauge wire, one powering a 220v 15 amp 15" planer and the other to my 220v 13.7 amp table saw (at least the wiring going to these is 10 gauge). Now that I have done some studying and reading and with the comments here, I see lots of problems in my panel. I should replace the 50 amp breaker with a 30 and a 20. The 30 powering my table saw and DC (1.75hp 220v 7.5 amps) on one circuit with two outlets. The 20 amp dedicated for the planer. I also see I "probably" shouldn't have two wires going to the 50 amp breaker, but that will be fixed with that breaker replaced. I also see the folks who wired the panel combined the common and bare wires on one bar instead of adding a bonding (I think the term is) bar connected by a bare wire back to the main breaker. i also found one 120v 20 amp breaker using 14 gauge wire. (And maybe there are more problems.) If I hadn't started this discussion asking some dumb questions, I never would have found all this. I truly appreciate all the comments. Hopefully I get it fixed before I burn the house down. Randy

Randy,

I'm not sure if I'm the only one reading the above this way, but it seems that you are wanting to replace your double pole 50 A 240V breaker with two breakers (20 and 30). Unless you get a very specialized breaker, you can't do that in your current sub panel. You have no need for any circuit over 30 amps. Unless you are going to run your planer and table saw at the same time, you really don't NEED two 240V circuits at all.

I will say this first: Your best bet is to install a new subpanel with at least 8/16 or better yet, 12 spaces/24 circuits so you have plenty of room to properly wire everything and leave some room for expansion. You could run two 30A circuits for the 240V stuff using 10ga wire which is relatively cheap, and have plenty of capacity.

If you are strapped for cash and want to use what you have, you can FOR THE MOST PART. You need to replace the 50A DP with a 30A DP breaker, ensure the wire running off of it is 10GA throughout the circuit, and daisy chain your 3rd outlet off of the closest receptacle. Running all three at once will probably trip the breaker, as it should. You will have to add a separate ground buss, and bring in another wire to feed the panel with a proper neutral (or a heavy red wire for the second hot leg, which should have been done the first time.)

Either way, you have some serious rewiring to do. I'm not sure you understand it completely yet, but hopefully you will soon. A GOOD electrician, standing next to you, not online, will be able to make it all make sense. I hope this makes sense, several others are basically saying the same thing. If it doesn't, don't try this yourself.

Dan

[Randall J Cox]

Ok, I dug deep into my wallet and I had an electrician over today to take a look at what I had and what I wanted to do. I told him to fix it. He is going to run a new #6 three wire (and ground) from the main panel to separate the commons and grounds in the subpanel. He will change out my 50 amp two pole breaker to two 30 amp two pole breakers (actually a quad), which in turn will end up with only one wire going into each breaker (as opposed the two wires per breaker that I have now). He will also add another 220 outlet. Unfortunately the main breaker panel is 100 feet from my subpanel, opposite ends of the house, that's a lot of 6 gauge cable. When done it will be all be safe. At least my two 220v circuits had 10 gauge wire already, the only thing that seemed to be right. I appreciate the members of this forum spotting all the issues I had. The electrician spotted one more, the small gauge of the bare ground wire that was handling current with all the commons and bare grounds together. Well, I learned a lot from all this. Thanks again, great forum. Randy

[Ben Rivel]

Ouch, 100FT is a long run for tall that copper. So what it all end up costing you if you dont mind telling?

[Marty Tippin]

That's great news, Randy. You'll be happier in the long run, even if it means a few bucks out of your pocket. Sounds like you'll be well prepared for whatever new machines you add to your shop.

[Chris Padilla]

This is money well spent, Randy, and you got an education to boot! Most excellent!

[Steve Meliza]

I'll echo what Dan Hahr said, upsize the sub panel while you're at it which will leave room for future additions. Here is a 12/24 panel that will accept your existing breakers - http://www.homedepot.com/p/Square-D-Homeline-125-Amp-12-Space-24-Circuit-Indoor-Main-Lugs-Load-Center-with-Cover-Value-Pack-HOM1224L125VP/202529821

[Randall J Cox]

That's great news, Randy. You'll be happier in the long run, even if it means a few bucks out of your pocket. Sounds like you'll be well prepared for whatever new machines you add to your shop.

Marty - Although it's tempting to install a bigger panel, I really can't stuff any more machines in my shop. This fix should do me, or any one who buys this place, fine. This will give me two 220v 30 amp circuits and two 120v 20 amp circuits in my small 16x18 shop (not counting the separate 20 amp circuits for lights and garage, outside of my shop, which is where my grinder and air compressor are located). Randy

[Mike Jungers]

You can run feeders in parallel, but they have to be a minimum of 1/0 if I recall, but more importantly that has nothing to do with this situation.:) If I rolled up on that panel, I'd replace it with a larger main lug panel to get more spaces, un-bond the neutral and ground and install a seperate ground bar, and place the 12-2 romexes on separate 20 amp 2-poles. For your 3hp loads, you need 10 awg wire on 25 amp breakers, or 30 amp breakers if they trip when you start them. Make sure the receptacles for the 240v circuits are rated the same as the breaker used, not higher or lower.

The NEC dictates that every part of a circuit is sized properly to prevent overloading any one part. That 50 amp breaker will let that 12-2 romex get waaaay too hot before tripping. Good on you for asking what to do and not burning your shop down.

I'd welcome you but it's my first post too!

Mike

[Randall J Cox]

You can run feeders in parallel, but they have to be a minimum of 1/0 if I recall, but more importantly that has nothing to do with this situation.:) If I rolled up on that panel, I'd replace it with a larger main lug panel to get more spaces, un-bond the neutral and ground and install a seperate ground bar, and place the 12-2 romexes on separate 20 amp 2-poles. For your 3hp loads, you need 10 awg wire on 25 amp breakers, or 30 amp breakers if they trip when you start them. Make sure the receptacles for the 240v circuits are rated the same as the breaker used, not higher or lower.

The NEC dictates that every part of a circuit is sized properly to prevent overloading any one part. That 50 amp breaker will let that 12-2 romex get waaaay too hot before tripping. Good on you for asking what to do and not burning your shop down.

I'd welcome you but it's my first post too!

Mike

Mike, first off welcome to the forum, this thread is my first here, it's a great forum for learning. What does your 1/0 mean? I tend to do lots of research before I actually do stuff because I want to understand what and why, it's just who I am. Then I'm usually comfortable with my decision and spending $. Randy

[Randall J Cox]

Well, electricians were here today, pulled 100 ft of new #6 three wire, added a couple of 220 outlets, installing new larger panel tomorrow and changing the 50 amp breaker to two 30 amp breakers for the two 220 circuits. Now have two outlets per 220 circuit. Will now be room for more breakers in larger panel for any future expansion. Thanks to forum members who alerted me to all the problems. Not going to be cheap, but will be safe. Randy

[Chris Padilla]

NOW let's see a picture of that properly-wired panel, Randy!! We can all ooh and aah over it instead of being shocked...literally. :D

[Randall J Cox]

Here's pic of new larger panel finished and buttoned up. Didn't make any changes on the 120v circuits, it was all involving the 240v side. Went from a single 240v 50 amp breaker to three separate 240v circuits. A 40, 30 and 15 amp. Now have four240v outlets, two outlets on the 30 amp circuit with one each on the other two. The DC and tablesaw will share the 30 amp circuit. The 3 hp 240v 15 amp 15" planer on the 40 amp circuit and the jointer will be on the 15 amp circuit - as soon as I change it over from 120 to 240v (it trips the 120v 20 amp circuit breaker now on startup about half the time, its an 8" 1.5HP Powermatic pulling 17/8.5 amps). As they pulled new #6 three wire, it now has separate bars for common and bare ground wires. And I have a couple of positions left empty. Think I'm good to go for a while. :) It was another learning experience. Now just have to pay the bill when it arrives!! ha Thanks again to all who commented! Randy




335706

[Chris Padilla]

Looks nice...how about a "behind the scenes" shot? :)

[Mike Jungers]

Sorry Randy I missed your question. 1/0 is a wire size, pronounced "one aught", and totally irrelevant now. I applaud your good judgement to hire the work out and not burn down your house. ;)

Mike

[Marty Tippin]

Now have four240v outlets, two outlets on the 30 amp circuit with one each on the other two. The DC and tablesaw will share the 30 amp circuit. The 3 hp 240v 15 amp 15" planer on the 40 amp circuit and the jointer will be on the 15 amp circuit

You might want to re-think how you're going to use the new outlets - since the DC runs at the same time as each of your other tools, I'd suggest putting it on it's own circuit (the 30A is perfect for that); the other tools can be arranged as you like as you're almost certainly going to use them only one at a time.

Can you confirm the wire gauge that the electrician used for the 30 and 40A 240V circuits? I'm also curious what kind of 240V outlets are on each of those circuits?

[Randall J Cox]

RE the 240v circuits and outlets. I went over what machines run at the same time with the electrician before we started. The DC only pulls 7 amps and the tablesaw 13.7 and they are on the 30 amp circuit. And of course they won't be turned on at exactly the same time. He put a 40 amp in for the planer as it runs at 15 amps and of course the startup will be higher. The lone 15 amp circuit will be for the jointer that will pull 8.5 when switched over to 240v. The 30 and 40 amp circuits both use 10 gauge wire. Twelve gauge at the 15 amp circuit. The machines really can't be moved around as there is nor more room nor a more efficient layout. I have looked for hours trying to be more efficient in my space utilization as its a small hobby shop. I have known this licensed electrician for probably the last 20 years, good guy. Does mostly large commercial jobs, only the 5/6 house he has worked on in years. He used to moonlight years ago, but not now with his kids of school age, does lots of football coaching. We did lots of talking and I asked lots of Qs while he was working. Randy

[Chris Padilla]

40 A needs at least #8, Randy. Generally speaking:

50A #6
40A #8
30A #10
20A #12
15A #14

[Randall J Cox]

40 A needs at least #8, Randy. Generally speaking:

50A #6
40A #8
30A #10
20A #12
15A #14

Yes, aware of that. As that circuit only has one outlet, the chances of pulling that kind of load with what I have is almost nil. He did say that if I plan to buy a high amp welder or something like that to let him know and he would adjust accordingly. Told him that probably wouldn't happen, no plans. I do plan to mod my little sheet i typed up and taped to the new load center to include wire size just to be careful for someone else or if my memory fails. It will be documented on the door to the panel. And to be totally safe, I could just change that breaker to a 30 amp. Randy