nikbrown Posted January 30, 2011 Report Share Posted January 30, 2011 Ok right now I have a sub panel in my shop. The entire shop is on 2 15amp 110 lines... needless to say I keep popping breakers. I have to turn out the lights to run the dust collector and the 110v contractor table saw at the same time I'm not afraid to to do my own 110v stuff but I stay away from wiring my own 220. (Plus they will have to pull wires from the house to the shop, probably). The current shop subpannel is full and has 60amp service (there is also a well pump runing off this panel). I'm betting I'll need more amps than that but I'm not sure. So I need to get an electrician out here to upgrade the shop. I plan on switching to 220v tools over the next few years. If I'm going to get someone out to upgrade the shop, what kind of service should I be looking for to future proof it? The master list of tools I can foresee ever having in there: 5HP table saw 1-2HP dust collector 1-2HP Band Saw 3HP Planer 3HP Jointer other small odds and ends. All of these will be single phase.... and of course only one tool at a time plus the dust collector. Just made a list to show I'm not dealing with anything exotic or industrial. So when i get the guy out here what do I need to tell him? Quote Link to comment Share on other sites More sharing options...
harryangel69 Posted January 30, 2011 Report Share Posted January 30, 2011 Questions What size wire is run to your shop sub panel? what size wire is run to your outlets in your shop? Is your shop attached or detached? (how far from panel to panel ballpark) What size breaker is powering your sub-panel? main-panel How many spaces for breakers are in your sub-panel? All panels that I have ever seen are 220 by nature. There is no difference between 110v and 220v wire there is just two hot legs (110+110=220). I just don't want you to get ripped off by an electrician. If feel up to it post a pic of your sub-panel with and without cover. Do I have to say shut off the power. Quote Link to comment Share on other sites More sharing options...
PaulMarcel Posted January 30, 2011 Report Share Posted January 30, 2011 If you already have a subpanel, you might be able to swap out half-size breakers for the full ones in your subpanel. For example, mine has a breaker that takes 2 slots, but it has connections for two 110V circuits and one 220V circuit meaning I get 3 circuits in what would have previously been one 220V circuit or two 110V circuit. You'll have 220V there; if nothing is 220V now, half-size breakers like the one I mention could be swapped in place for two full-size breakers and get you and extra 220V circuit. Biggest concern is that if the breaker on the main is 60A, you won't want to exceed that on the subpanel. Sure you could 'upgrade' the breaker in the main panel, but you have to be certain that the feeder wire between panels is sized correctly (conductor sizes, ground size, and that the conduit between the two isn't too full... there's a chart for that). I wrote a rather lengthy blog article on running a subpanel then wiring it up just last night. It covers those size calculations and where to get the numbers as well as how to do the wiring in the panel. Sorry, it's a bit long... read it here for the insomniacs Quote Link to comment Share on other sites More sharing options...
dlamulle Posted January 30, 2011 Report Share Posted January 30, 2011 Ok right now I have a sub panel in my shop. The entire shop is on 2 15amp 110 lines... needless to say I keep popping breakers. I have to turn out the lights to run the dust collector and the 110v contractor table saw at the same time I'm not afraid to to do my own 110v stuff but I stay away from wiring my own 220. (Plus they will have to pull wires from the house to the shop, probably). The current shop subpannel is full and has 60amp service (there is also a well pump runing off this panel). I'm betting I'll need more amps than that but I'm not sure. So I need to get an electrician out here to upgrade the shop. I plan on switching to 220v tools over the next few years. If I'm going to get someone out to upgrade the shop, what kind of service should I be looking for to future proof it? The master list of tools I can foresee ever having in there: 5HP table saw 1-2HP dust collector 1-2HP Band Saw 3HP Planer 3HP Jointer other small odds and ends. All of these will be single phase.... and of course only one tool at a time plus the dust collector. Just made a list to show I'm not dealing with anything exotic or industrial. So when i get the guy out here what do I need to tell him? I think the main problem you have is several tools on the same breaker. You should be able to run everything you have there on a 60 amp sub panel, but if it was me I'd go up to 80 or even better 100. First, I think you need to have all your lighting on one breaker, then your 220 tools; planer, jointer and table saw can be on the same 220 circuit if need be because you probably won't be running them at the same time so you're safe. The DC on a dedicated breaker would be wonderful. If the band saw is 110 it can go on any of the remaining circuits that will be used as general plugs. These circuits are for routers, jigsaws etc. If the bandsaw is 220 then perhaps you could have 2- 220 circuits and have the tools you would never use together on one or the other. Hope this helps. Dave Quote Link to comment Share on other sites More sharing options...
ssrt3 Posted January 30, 2011 Report Share Posted January 30, 2011 Paul great blog post. Ok the only thing I have to add to that post is put an acass for that 90 that you put in the wall that is code if it has a cover that can be removed it has to be open to service. So put a small door on it don't drywall over it. I would recmend that you put in 100amp service in your grage just for groth. Look at it like this its a one time purchase better to over do it now than under do it when you need more circuts later it will be the best 200-300 dollars you spend. For your upgrade and don't be nervis about 220 its The same as 110 you just have to hots to the same a/o. (Sorry about spelling doing this on my cell phone with fat fingers) Quote Link to comment Share on other sites More sharing options...
nikbrown Posted January 30, 2011 Author Report Share Posted January 30, 2011 This is the subpanel in the shop. The shop is detached and about 20ft from the house. looks like the wire is run through an buried 3" PVC pipe. The breaker in the main panel in the house is 60AMP and it looks like the well pump sub-subpanel (next to this) is 30AMP (the well doesn't get used much, it's only for outside usage). I guess in theory I could just shut off the breaker in the house and replace this subpanel with a larger one with more room to grow and I could run new lines myself. My only concern is the 60 AMP service. I guess if I decide I need more than 60 AMPs at a later date I could get someone to come pull a heaver gauge wire to the pannel I install. Quote Link to comment Share on other sites More sharing options...
PaulMarcel Posted January 30, 2011 Report Share Posted January 30, 2011 That's the exact same load center I put in. You can get those half-size breakers I mentioned to give you some 220V circuits without changing the panel. A bigger concern is that your panel has a number of grounds going to the neutral bus. A subpanel needs to separate the neutral and ground bus running them both back separately to the main panel. I'd correct that, definitely. Likely whoever ran the run from the main panel ran 4 wires (2 hots, neutral, ground) but whoever wired the panel didn't know the differences between a main and sub panel (in a main, ground and neutral share a bonded bus). What gauge wire is in the PVC? You might be able to switch the main breaker. Thanks for the comments, ssrt. I didn't show a final picture of that 90 angle, but it is mounted to the surface of the drywall. The cutout was for me to gain access to the cavity. Good point; I'll take a picture and add it to that posting. Actually, someone asked about GFCI clarification so I'll make another posting tonight about some of those details. Quote Link to comment Share on other sites More sharing options...
harryangel69 Posted January 30, 2011 Report Share Posted January 30, 2011 Yea, looks like that panel is maxed out. options i see are: new sub-panel - you should be alright with the 60amp for now you just need some more spaces to run a dedicated line for a couple for tools that don't get used all at the same time. A 20amp outlet just for a dust collector, bandsaw, or table saw. That could solve your problem for now, but no room for upgrade later. This could be done for about $100 and an upgrade could just be apart of the next big tool purchase. I don't live in your area but here, in a detached shop, in that situation I would set a second meter. Unlimited upgrade options for the future. You could do the same with a new wire and 100amp subpanel but here a second meter would be cheaper. Down side to a second meter is there may be cost for you that I am not aware. My electric company would set a meter for nothing making it an easy option. Your wife will know exactly how much it costs to run your shop every month. May have to pull a permit if an electrician is brought in and there may be other things that need to be done to meet code. Resist the urge to install another cheater breaker your panel is only rated for six and you have seven. Take all advice from the internet with a grain of salt. I don't know what is needed to meet your local code, and that even varies between inspectors. Always get some advice from a local pro. An estimate is cheap. Quote Link to comment Share on other sites More sharing options...
nikbrown Posted January 30, 2011 Author Report Share Posted January 30, 2011 Wire running form the main panel is 3 x 6gauge stranded. So 60 AMPs is max if any of the online carts are correct. Looks like it's 2 lives and 1 ground. Quote Link to comment Share on other sites More sharing options...
PaulMarcel Posted January 30, 2011 Report Share Posted January 30, 2011 With a reasonable "ambient temperature" correction, 6ga runs can handle 65 or so amperes. Just three wires? Kinda strange. Seriously, there should be four. The key is what you'll run simultaneously. Get your pump rating and consider it always on then see how many amperes you have left. That 50A 220V breaker in the middle is likely the pump. If it needs 50A on your 60A box, you don't have much room. Between the issues you can see on the picture (sorry, it's grainy) and the thought that there are just 3 wires going to it, have an electrician inspect it; to me, there are things done incorrectly on it. He might pull new wires. In 3" PVC, you could easily handle lower gauges without capacity issues. The load center box itself is pretty inexpensive. If you get the same brand, the existing breakers could get reused. Likely better in the long run. Personally, if I was married, I wouldn't want my wife having an itemized power bill for my shop since I doubtfully would have one for her "shoes". Quote Link to comment Share on other sites More sharing options...
ssrt3 Posted January 31, 2011 Report Share Posted January 31, 2011 With a reasonable "ambient temperature" correction, 6ga runs can handle 65 or so amperes. Just three wires? Kinda strange. Seriously, there should be four. I do agree with you there should be four, I did a job in a small town where the inspector did not want four he only wanted the three and told me to disconnect the ground in the sub-panel since the garage was not attached to the house he seems to think its not needed and would not pass the inspection till i removed the ground wire. so as you said check your local codes and check to see what the inspector wants done. Quote Link to comment Share on other sites More sharing options...
.thumb.png.f1505d235090fa2186090ae6cc818259.png)
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.