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Forum topic by Stewbot posted 07-05-2015 04:44 AM 985 views 0 times favorited 13 replies Add to Favorites Watch
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Stewbot

195 posts in 543 days


07-05-2015 04:44 AM

I’m just getting a shop together, and like many, work out of a two car garage. I have a 220 and I think just one 110 circuit, however the 220 is dedicated to the washer dryer. In terms of larger machines, I’ve got a 11/2 hp dust collector, 11/2hp bandsaw, 1hp drill press but will be adding other larger machines as time passes. I have a compressor and table saw, and many hand power tools and bench top tools, but they are all pretty light duty. The point is right now I’m basically confined to a single 20amp( I believe) circuit, thus can really only run a couple lights and a larger machine at once. I cannot really run my DC because I figured I’ll be pulling too many amps while running with any other larger shop tools. My DC basically already dims the lights when I turn it on alone. Anyway, I would like to add at least one more 110 and 220 circuit. In the future I’m sure I’ll eventually wire some machine to 220 but at the moment don’t really need to, as the tools I own and plan to buy come pre-wired for 110. However it is to my understanding that should I wire my machines for 220 they will pull less amps, thus needing fewer 220 runs than if I ran them 110? Regardless, any work I do just depends on the over-all bid, but really am unsure about how much something like this would cost. Basically I am looking for the most efficient way to run my handful of machines with the least amount of new lines installed.

I’m just seeking general advice or recommendations regarding my future electrical ventures. Im sure it will cost a fair amount to get this work done, and that’s why I’m looking for advice as to what is really necessary for a small shop with only about a half dozen larger machines (all between 1-2 HP). I don’t really mind plugging in and unplugging machines etc. however it would be nice to have dedicated outlets for everything. I also don’t care about running lines behind the Sheetrock and will consider running the lines myself (in the proper casing) and having an electrician make the connections to the panel. Which luckily is right on the other side of the garage wall.

Anyway, just hoping to get any suggestions or insight on similiar experiences.

Thanks

-- Hoopty scoop?


13 replies so far

View Firewood's profile

Firewood

93 posts in 1093 days


#1 posted 07-05-2015 05:17 AM

Brendan, Like you, my basement shop was running on a single 120v 20A circuit that made it nearly impossible to run more than one tool at a time. In preparation for a new table saw, I upgraded my shop with a dedicated 60A sub panel.From that I installed 5 surface mounted quad boxes so the bottom of them was just over 48” off the floor. Each box has 2 duplex oulets that are on seperate 20A breakers. 4 of the boxes share 2 breakers and the 5th has a 20A 120v duplex and a 20A 240v outlet for the saw. There is still plenty of space for expansion. The shop lights are still fed from the main panel. That way I can shut the sub off completely without killing my lights. Unfortunately, I can’t give a good estimate on cost because my master electrician neighbor came over to help and didn’t charge anywhere near what it would have cost otherwise.

-- Mike - Eagle, WI

View TheFridge's profile

TheFridge

5764 posts in 946 days


#2 posted 07-05-2015 05:42 AM

As far as home runs go, it’s about the same. Whether it 120 or 240 it should be dedicated for your bigger stationary equipment. Though it might be frowned upon i put my table saw and jointer on the same ckt because I can and they will never be ran at the same time.

120 vs 240. Less amperage = smaller wire. And a little bit more torque or hp though all the calculations say otherwise.

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

View BurlyBob's profile

BurlyBob

3646 posts in 1725 days


#3 posted 07-05-2015 06:27 AM

Brendan, there’s a couple of retired electricians on Lumberjocks, Topamax and exelectrian for 2. Talk to those guys they won’t steer you wrong.

View Stewbot's profile

Stewbot

195 posts in 543 days


#4 posted 07-05-2015 07:51 AM

Thanks for the replies.

Firewood, I think a separate subpanel would definitely be the way to go, the system you explained sounds very useful and well planned out. A sub panel in the shop also would seem easier to tap into at a later time, as long as it had the extra room. However, Being that I have so many tools on my wish list, as well as necessary electrical and DC systems to install, I’m going to need to get crafty with my route as well as possibly make a few sacrifices. Sure wish I had made friends with more electricians right about now…but come to think of it, I do know a couple contractors who could probably lend a hand in steering me in the right direction.

With that said, thanks for the info Bob, it’s good to know there are some retired electricians on the forum and would be happy to get thier thoughts.

Regarding what the fridge mentioned, I had something similiar in mind in terms of sharing circuits for multiple machines. I’m the only one who uses the shop, my lady does her crafts in thier as well but aside from that, it’s pretty low key and I wouldn’t anticipate needing to run more than two machines at a time. My DC and whatever machine I’m on and lights of course. I’m obviously not too familiar with electrical, but having been in the trades for a handful of years , I’ve sort of picked a few of the basics (or at least I’d like to think so). with that said, the first thing I’ve learned is to leave anything in question to the pros. Probably the most I would be able to do is run the wires and conduit, and possibly wire the 110 boxes. any panel work, I would leave to the professionals.

Anyway, I was thinking about trying to keep it simple and minimal by running 2-3 new 110 lines from the main panel (which I think has some room) rated at (30 amps?) to give me 3-4 in total, and then another 1-2 220. Although it sounds like it’s a bit frowned upon not having dedicated lines, I was thinking about only running a dedicated feed to my DC. As long as not having dedicated feeds to every machine it’s not a hazard and more of just an inconvenience, I’d rather keep it as simple and budget friendly as it can be….speaking of simple, it’s late, I’m confused and now starting to think maby I should just buy some hand planes and oil lamps instead.

Thanks again.

-- Hoopty scoop?

View Pezking7p's profile

Pezking7p

3097 posts in 1111 days


#5 posted 07-05-2015 12:49 PM

Run a dedicated for your d/c and possibly your air compressor. Other than that, make the outles convenient. I have three 20A circuits in my shop and a separate lighting circuit (I don’t have a d/c) and have only ever had an issue when I was running my jointer and the air compressor happened to kick on at the same time due to a small leak…the circuit didn’t trip but both machines struggled until the air compressor motor got spun up. Might have played out differently with a larger air compressor.

I think a handful of circuits is plenty.

-- -Dan

View Crank50's profile

Crank50

173 posts in 1036 days


#6 posted 07-05-2015 04:42 PM

Most home breaker panels are full, or nearly full, of circuits already so it is not likely you could run more than a single additional circuit or maybe two. If that is the case, you need to make that circuit do the most work possible by using it to feed a sub-panel.
If you have no more open slots in your main panel you may be able to replace some of the single breakers with “double singles”. Those are special breakers that connect two circuits in the place of one single pole breaker. They allow you to create a space by compacting some of the original spaces. If your panel is a brand or age that does not have double singles available then you might have to replace the 220V circuit for your washer/dryer with larger wire and breakers to feed a sub panel which will then have to supply the old washer dryer outlet. Bottom line, there are many ways to do this and a sub-panel is the best way to go.

As far as number of circuits, you need the lights separate from all power tool circuits. You need at the very least to have two outlet circuits with as many outlets on them as you have room and money to install. Then you need separate circuits for large machines and two of those large machines might need to be 240V.

I have seen other folks say things like they have five or six 240V circuits, but that seems like a waste to me unless you have more than one person working in there.. I have a Table saw, 6” joiner, band saw, 13” planer, drill press, mortising machine, air compressor and dust collector along with many more plug in tools and all run on 120V. I do hope to upgrade the table saw to a 3hp and some day might have a 2 or 3 hp band saw which will both need 240V. The only time I need two tools at once is for the dust collector and what ever is making the dust.

One thing I did, and have been very happy I did, it was to make all my outlet boxes quads. Each box has two duplex outlets in it and they are each on a different circuit. So, if I plug my router in the left side I plug my shop vac in the right side they are on different breakers. Works great this way.

View Stewbot's profile

Stewbot

195 posts in 543 days


#7 posted 07-05-2015 06:27 PM

Pezking, I was gonna mention my compressor situation but forgot to. That will be similiar to a bench top tool in terms of its manner in which I use it. I turn it on when i need it, and it’s off when I’m done. It’s just a little Makita mac700 and I’m sticking with it. It serves me well, and aside from finish guns and car tires, it supplies nothing else. In short, I don’t have a 50gallon compressor to worry about kicking on randomly. My initial plans were to just add a few extra line from my main panel, which I believe has the room, but I’ll know for sure I guess when I get an electrician here.

As far as number of circuits, you need the lights separate from all power tool circuits. You need at the very least to have two outlet circuits with as many outlets on them as you have room and money to install. Then you need separate circuits for large machines and two of those large machines might need to be 240V.

- Crank50

Crank, thank you for the thorough reply.

Are you saying that each large machine needs a dedicated circuit? Or that large machines need to be separate from the other circuits you mentioned, but multiple machines can be on a single circuit?

If large machines need thier own circuits:

Assuming I wire it how you mentioned (lights separate from tools, a couple lines feeding multiple boxes etc.) but do so differently for large machines, in the sense that I do not have a dedicated feed to every machine, with the exception of my DC. If these machines share a circuit but are not operated simultaneously, what would be the disadvantages in this?

I appreciate all the feedback. I’m not looking for a specific answer that I want to hear, but more so just trying to fully grasp the advantages or disadvantages of sharing multiple machines on one circuit and find out what other people’s systems are, as I know my situation is probably like many others who work out of a garage. Price is a factor in this, but I will not compromise on safety to save some money. Considering the lack of circuits I’m starting with, and the amount I’ll need to add, I’m thinking a sub-panel may be in my future. Depending on what my electrician says. Anyway, really any amount of new lines will be a serious upgrade for my current situation.

Thanks again.

-- Hoopty scoop?

View Holbs's profile

Holbs

1371 posts in 1489 days


#8 posted 07-05-2015 08:15 PM

I went thru the same as you did. Here is my beginning / end results.
http://lumberjocks.com/Holbs/blog/34833
For a 2 car attached garage, I would recommend everyone do their own electrical (as compared to a separate structure, 3 phase wiring, etc). If truly skittish, you can do all the hard labor yourself by running the wire, or installing conduit, installing boxes… and hire an electrician to terminate everything.
Keep a lookout at local auctions for electrical boxes, romex, conduit, etc. You would be very surprised at what you can gather.
If you are limited to what you can add / do…. #1 helpful hint would be to add a 20amp circuit middle ceiling and add a retractable cord reel up there. It really is a LIFESAVER!

-- Yes, my profile picture is of a Carpenter Bee! The name is derived from the Ancient Greek "wood-cutter"

View Stewbot's profile

Stewbot

195 posts in 543 days


#9 posted 07-05-2015 08:32 PM



I went thru the same as you did. Here is my beginning / end results.
http://lumberjocks.com/Holbs/blog/34833

- Holbs

Thanks for the link. Unless I’m mistaken, I noticed you had made a comment that it is not code to run Romex inside of conduit? What type of wiring do you run inside conduit?

-- Hoopty scoop?

View Ron Ford's profile

Ron Ford

200 posts in 1192 days


#10 posted 07-05-2015 08:41 PM

Assuming you do install a separate sub-panel (smartest option, in my opinion), buy one that has way more slots than you think you will ever use. You can be certain that, over time, you’ll need/want extra circuits.

Ron

-- Once in awhile I make something really great. Most days I just make sawdust.

View TopamaxSurvivor's profile

TopamaxSurvivor

17654 posts in 3135 days


#11 posted 07-05-2015 11:47 PM

You use single conductors in conduit.

If your motors are noticeably slow on start up, you should go to the higher voltage. That should have a significant impact on light dimming.

-- Bob in WW ~ "some old things are lovely, warm still with life ... of the forgotten men who made them." - D.H. Lawrence

View Crank50's profile

Crank50

173 posts in 1036 days


#12 posted 07-06-2015 02:00 AM



Are you saying that each large machine needs a dedicated circuit? Or that large machines need to be separate from the other circuits you mentioned, but multiple machines can be on a single circuit?

If large machines need thier own circuits: Assuming I wire it how you mentioned (lights separate from tools, a couple lines feeding multiple boxes etc.) but do so differently for large machines, in the sense that I do not have a dedicated feed to every machine, with the exception of my DC. If these machines share a circuit but are not operated simultaneously, what would be the disadvantages in this?
Thanks again.
- Stewbot

The only electrical code issue would be for hard wired machines with motors. Those machines MUST be on separate circuits. Air compressor and a dust collector might be wired this way. A table saw and joiner and planer can share a circuit as long as you understand that circuit will pop the breaker if you run them at the same time. I plug my machines in as I need them and unplug them before moving to the next machine. I try to keep everything unplugged when I’m not in the shop. Dust collector is the obvious exception here.

Bob (Topomax) answered the conduit question. I might add that stranded THHN single conductor #12 AWG is what I ran to all my outlets, in conduit, and I installed 20 amp rated outlets.

View Stewbot's profile

Stewbot

195 posts in 543 days


#13 posted 07-06-2015 06:30 AM


You use single conductors in conduit.

If your motors are noticeably slow on start up, you should go to the higher voltage. That should have a significant impact on light dimming.

- TopamaxSurvivor

Ok I see, thanks.

The only electrical code issue would be for hard wired machines with motors. Those machines MUST be on separate circuits. Air compressor and a dust collector might be wired this way. A table saw and joiner and planer can share a circuit as long as you understand that circuit will pop the breaker if you run them at the same time. I plug my machines in as I need them and unplug them before moving to the next machine. I try to keep everything unplugged when I m not in the shop. Dust collector is the obvious exception here.

Bob (Topomax) answered the conduit question. I might add that stranded THHN single conductor #12 AWG is what I ran to all my outlets, in conduit, and I installed 20 amp rated outlets.

- Crank50

Thanks for the info. I think I’ve got a good idea on how I’d like to improve my single circuit workshop at this point.

Thanks everyone for all the input. It is definitely appreciated.

-- Hoopty scoop?

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