Any electricians out there?

[Clay Mosby]

I have a small woodworking shop in a garage with just the standard suburban home wiring in it. The result is I have to be careful which machines I run at the same time so I don't pop the breaker.

 

I'm thinking of having a small sub-panel added for just the garage with maybe 4-5 circuits on it. I know I need a licensed electrician to do this, I was just wondering if anyone might have a ball park of what sort of cost I could be looking at?  Haven't started infoweb searches yet.

[Pat Riot]

I was going to do this in Oregon but never followed through. I had one guy estimate about $500 and another $800. I could do the work myself but I wanted it done by a licensed electrician. 
I would have gone with the $800 guy because a 62% difference in price might mean the $500 guy didn’t know what he was doing and that could end up being a problem. 

[Pat Riot]

I should add that my main breaker panel was in the garage and I wanted 3 quad outlets with a 20 amp breaker on each set of outlets. 
 

 

[Linn Keller, SASS 27332, BOLD 103]

You've the right idea with quad outlets.

As a rough figure, calculate the most of them you will need, then double it.

Wish I had!

[LawMan Mark, SASS #57095L]

When I built a shop back in the 90s, I put a 100 amp breaker inside my house, and had an electrician run heavy cable  from there to the shop, where he hooked into a sub panel.  I then ran the wiring from there.  I put a 110 plug in ever four foot on the walls, with no more than 4 receptacles on a circuit.  I put a 110 receptacle outside each door.  I put a 220 receptacle in 4 locations, where I could run a variety of woodworking tools with no more than a 20 foot extension cord.  My work table had quad electrical outlets on two sides.  The only thing I wish I had done differently, is that I wired my air compressor up inside the shop.  I'd put it outside somehow.  Dang thing was awful noisy.

 

Lost that shop in a divorce sale a few years ago.  Sure do miss it.

[Cholla]

Your price is going to vary on how far the garage is from the main panel and what’s in the way that the electrician is going have to deal with. A sub feed is going to require a four-wire feed. If I remember correctly the wire needs to be 4 awg copper. 

[Marshal Mo Hare, SASS #45984]

I can understand a variance in price if you pound the ground in.

[largo casey #19191]

Here where I live you can go to the City & take a test .If you pass you can do your own home wiring.

                                                                                                                                                                         Largo

[Clay Mosby]

I need to go through my power tools and add up the power requirements. So far it's:

table saw

band saw

drill press

oscillating sander

planer

dust collector

scroll saw

 

and assorted lights, a fan or two and in the winter a quartz heater.

Granted I'd only be running the power tools one at a time, but sometimes the heater coming on while sawing will trip the breaker.

[Cypress Sun]

Clay

The max you would need at the garage is a 50 amp, 120/240 volt, 4 wire circuit with a 6/12 circuit panel. The wire would need to be at least 3-#8 wires with a #10 ground depending upon how far from the panel your garage is and how much load you will be continuously using. If your garage is detached from the house, you will need a service disconnect (sort of a main breaker) for your garage panel. As others have said, you'll want various quad receptacles around the garage with a maximum of 2 - quad receptacles per 20 amp circuit.

 

The cost depends upon many factors, how far of a run is it for the main wire/is your main panel able to handle the additional load/does your main panel have two more spaces for the garage panel/what type of wire may be used in accordance with local codes and various other factors.

 

Generally figure this for your budget if your garage is attached to the house..........

- Panel with wire $800 to $1000

- Each pair of quad receptacles on their own circuit $100 to $200 each

 

- Best case scenario $1400

- Worst case scenario $3000

 

These prices are based on the factors above. I'm a 40 year electrician and have done plenty of estimates just like this before.....of course I can't see your particular project however. In any case, unless you are familiar with electrical wiring, procedures and codes, please use an real electrician. The life and house you save may be your own.

[Cypress Sun]

 

I need to go through my power tools and add up the power requirements. So far it's:

table saw

band saw

drill press

oscillating sander

planer

dust collector

scroll saw

 

and assorted lights, a fan or two and in the winter a quartz heater.

Granted I'd only be running the power tools one at a time, but sometimes the heater coming on while sawing will trip the breaker.

 

See my above post. As far as the equipment listed, remember that all of this will not be running at the same time. From what you have listed 50 amp will be more than enough service for the garage.

 

PS: you forgot a air compressor.

[The Original Lumpy Gritz]

Add 10% to usage for tool startup.

Is this shed on a 15A or 20A circuit? 

Have a pro come out and see what he/she sayz... 

OLG 

[Doc X]

"The cost depends upon many factors, how far of a run is it for the main wire/is your main panel able to handle the additional load/does your main panel have two more spaces for the garage panel/what type of wire may be used in accordance with local codes and various other factors." 

 

While not an electrician myself, Dad was for 37+ years so I picked up more than you would in a Holiday Inn Express.      Cypress Sun is spot on! Please be sure to have a pro do your work, there is way more involved than just running some wires. Electrical is the number one cause listed on fire reports for a good reason. Dad always told me not to fear it, but you dang well better respect it!

[Blast Masterson]

High amperage inductive load appliances/tools should be on their own circuit (like a compressor, welder etc.).

 

Voltage drop from line wire or motor start up increases amperage draw making the breaker trip.

 

Wire size is about type of wire and conductor material.

 

Breaker size is to protect the wire down stream of the breaker not the tool amperage attached to it.

 

Make sure your 20 amp outlets are not on the same phase from the panel.

[Yul Lose]

In my shop I’ve got the 220v dust collector on its own circuit, you might want to do that also as it should be running when your power tools are running

[Clay Mosby]

The garage is attached, everything I own is 110V, and yes, it will in 99% of the cases one tool and the dust collector running, plus maybe a portable AC in the summer or my quartz heater in the winter.

My totally uneducated guess was in the $2k-$3k range.  I just sent a quote request to a local electrician/shop.

 

Thanks for the info guys.

[Barry Sloe]

If you can,  do all the wiring yourself and have the licensed electrician do an inspection and final connection.  This would save you alot of labor costs.

 

BS

[J.D. Daily]

 

Your price is going to vary on how far the garage is from the main panel and what’s in the way that the electrician is going have to deal with. A sub feed is going to require a four-wire feed. If I remember correctly the wire needs to be 4 awg copper. 

#4 copper is good for a 85A.  For the 4 separate 4 gang 20A duplex AFI/GFI receptacles 2 spaces are required to install quad 20A ckt. bkr.plus 2 spaces for each 220V ckt.  The smallest amperage panel that would have enough spaces is 100A which requires #3 copper.  If the location is far from the main panel you might want to include a main breaker; so, that you can deenergize the panel locally.  Otherwise it is prudent to have a nameplate (sign) that indicates the location of the disconnect.  I recommend using twistlock receptacles for 220V unless it's for a welder.

P.S. tell the licensed electrical contractor you want copper conductors only.  Typically if they have their druthers anything over 30A will be aluminum.

[Cypress Sun]

 

#4 copper is good for a 85A.  For the 4 separate 4 gang 20A duplex AFI/GFI receptacles 2 spaces are required to install quad 20A ckt. bkr.plus 2 spaces for each 220V ckt.  The smallest amperage panel that would have enough spaces is 100A which requires #3 copper.  If the location is far from the main panel you might want to include a main breaker; so, that you can deenergize the panel locally.  Otherwise it is prudent to have a nameplate (sign) that indicates the location of the disconnect.  I recommend using twistlock receptacles for 220V unless it's for a welder.

P.S. tell the licensed electrical contractor you want copper conductors only.  Typically if they have their druthers anything over 30A will be aluminum.

 

Sorry J.D., This is incorrect for a residential dwelling with a single phase service.

 

- As per National Electric Code 310.15(B)(7) the service entrance conductor can be rated at 83% of the load. Therefore the 100 amps X 83% = 83 amps hence making a #4 THHN type wire permissible by code. Clay's needs are well below that so a a 50 amp, single phase panel will more than meet his needs.

 

- A panel's amp rating has nothing to do with the feeder feeding it as long as the feeder wire has the proper overcurrent protection (ie breaker or fuse). A 50 amp circuit feeding a panel rated at 100 amps is perfectly permissible by code as long as the load on the panel is less than 50 amps. 

 

- A main breaker at the garage sub-panel is not required as the garage is attached to the house where the main panel is located. It would not be a bad idea though to include this extra breaker in the panel so the entire workshop could be shut down with one throw of the breaker but is not required and would incur more costs to the job for additional spaces in the panel.

 

- The nameplate is an good idea to indicate where the sub-panel is fed from although not required.

 

- The twistlock receptacles and/or male cord ends are expensive and not required. Although not a bad idea, normally such equipment is hard wired. 

 

- The copper conductors statement is absolutely dead on. Aluminum wire is a future problem (and possible disaster) waiting to happen. How the powers to be ever allowed aluminum wire under a 4/0 awg to be used is beyond me. I personally will not install aluminum wire under 4/0 unless the owner of the company I'm working for forces me to do it. Even then, he'll have to listen to considerable bitching about it.

[Muleshoe Bill SASS #67022]

You could always hire the guy who did this

[Muleshoe Bill SASS #67022]

Clay use this as a guide to self wiring the panels

[Cypress Sun]

 

You could always hire the guy who did this

 

It means the same thing as wearing a red shirt while beaming down to a new planet on Star Trek. 

 

A burning up neutral is a very common problem especially when the phases are grossly out of balance. This particular problem looks to be caused by a loose connection on the bolt or bad crimp.

[Cypress Sun]

 

Clay use this as a guide to self wiring the panels

 

Nice, neat job for a handyman.  At least the panel on the right is a Square D, QO type panel.

[Dutch Nichols, SASS #6461]

Pull permits  and have a journeyman electrician do the work

If something goes wrong later on, fire, accident , etc. at least your insurance will cover you.

Most folks don't realize if the above happens the insurance company will look for

reasons to deny coverage. 

[Dirty Low Down sass 23492]

Gotta agree w/Dutch on that---anytime something happens and if do it yourself is involved insurance co. gonna say "NO WAY JOSE"---and if you gonna  get it done GO W/ HIGHEST AMPERAGE CAPABILITY YOU CAN AFFORD------at least twice what ya think ya gonna be using---------ya dealing w/ BIG BOYS TOYS & as ya go along ya gonna pick up more & bigger toys----later on ya be glad ya did!!!

[Clay Mosby]

Thanks for all the info guys.  I've reached out to a couple licensed electricians but haven't heard back yet.

[J.D. Daily]

 

 

Sorry J.D., This is incorrect for a residential dwelling with a single phase service.

 

- As per National Electric Code 310.15(B)(7) the service entrance conductor can be rated at 83% of the load. Therefore the 100 amps X 83% = 83 amps hence making a #4 THHN type wire permissible by code. Clay's needs are well below that so a a 50 amp, single phase panel will more than meet his needs.

 

- A panel's amp rating has nothing to do with the feeder feeding it as long as the feeder wire has the proper overcurrent protection (ie breaker or fuse). A 50 amp circuit feeding a panel rated at 100 amps is perfectly permissible by code as long as the load on the panel is less than 50 amps. 

 

- A main breaker at the garage sub-panel is not required as the garage is attached to the house where the main panel is located. It would not be a bad idea though to include this extra breaker in the panel so the entire workshop could be shut down with one throw of the breaker but is not required and would incur more costs to the job for additional spaces in the panel.

 

- The nameplate is an good idea to indicate where the sub-panel is fed from although not required.

 

- The twistlock receptacles and/or male cord ends are expensive and not required. Although not a bad idea, normally such equipment is hard wired. 

 

- The copper conductors statement is absolutely dead on. Aluminum wire is a future problem (and possible disaster) waiting to happen. How the powers to be ever allowed aluminum wire under a 4/0 awg to be used is beyond me. I personally will not install aluminum wire under 4/0 unless the owner of the company I'm working for forces me to do it. Even then, he'll have to listen to considerable bitching about it.

The feeder from the main panel is not service entrance.  Also the minimum feeder rating should be based on the total connected load with a diversity factor applied.   In garages and shops where the loads are wood working tools you should apply service factors greater than 1.0.  For example a table saw with a 120V 1.0 capacitor start motor will trip a 15A branch circuit breaker when cutting green lumber unless the feed rate is very slow.  "Been There Done That" many times in the past 50 years.  That is why I didn't install less than 20A rated circuits in my shop building. 

[Cypress Sun]

 

The feeder from the main panel is not service entrance.  Also the minimum feeder rating should be based on the total connected load with a diversity factor applied.   In garages and shops where the loads are wood working tools you should apply service factors greater than 1.0.  For example a table saw with a 120V 1.capacitor start motor will trip a 15A branreaker when cutting green lumber unless the feed rate is very slow.  "Been There Done That" many times in the past 50 years.  That is why I didn't install less than 20A rated circuits in my shop building. 

 

While the feeder to the garage is not service entrance, the residential application still applies as it is still a service that supplied to a residential garage. For residential applications there are no additional factors applied such as 125% of additional load or many other factors that do apply for commercial locations. Doesn't mean that I agree with it but that is the code as per NEC.

 

If the circuit is installed as a dedicated circuit for say a table saw that has a amp rating of 15 amps, then the circuit breaker could be a 45 amp breaker on a #12 wire (250% of the amp rating) due to motor start up load. A fuse could be up to 175% of start up load on the same #12 wire. This DOES NOT apply to a general duty branch circuit.

 

There is huge differences between commercial locations and residential locations in reference to NEC (National Electric Code). If Clay were doing woodworking on a commercial basis and had a workshop like Yul Lose, I certainly would not suggest the residential formula's for his application. 

 

If you can show me, in the code, that any statement that I have made is incorrect then please do. Even after 40 years of doing electrical work, I still love to learn new things..........and I've been wrong before.

 

CS

[Clay Mosby]

Got the first quote today. $3684 for 3 20A circuits with quad boxes. After discussing the machines and their usage he recommended the three circuits and because there is room on the main panel I won't need a sub-panel. One circuit for the dust collector, one for the machines and one for a space heater/portable AC. Got requests in for two .ore quotes.

[Cypress Sun]

That seems kind of pricey for around here. I can't say about your location. Get the other quotes and see. I'm interested in hearing what the quotes are. Find out if he is using romex type wire or conduit.......that makes a big difference in price.

[Clay Mosby]

I kinda doubt we'll go with this guy. They quoted an extra $480 to put in quad boxes rather than duplex. Seemed awfully high!

 

[Marshal Mo Hare, SASS #45984]

Thinking about this, I would have 4 20A 120V circuits, call them A B C and D.  4 quad boxes with 2 duplex outlets each being served but two different circuit. Put a box on each wall, N wall served by circuits AB, south wall CD, East wall AC, west wall BD.  If the dust collector was going to run all the time, I might do it something special for it, like a dedicated circuit.

 

 

[Tequila Shooter]

Maybe I'm the odd man out.  When I put in my workshop in an outside shed I ran the power to it myself.  I put a 100 amp breaker in the main box, buried a conduit and ran THWN in it with a 90 amp main breaker in the sub-panel.  I've got an RV out there so I put in a 50 amp circuit to it from the sub-panel.  I also put in an outlet for my welder, another for the air compressor, a couple of others for A/C, lights, and tools.  Before everyone says that it's overloaded, the RV never draws 50 amps even with all the A/C's running, the compressor is a smaller portable one.  I've never had a breaker trip or had any problems.  I've got nothing against electricians, I'm just cheap and willing to do the work to save $$.

 

Now the the criticism begin.   

[Three Foot Johnson]

When I built my last shop, 32'x56', I leapfrogged the six 110v outlet circuits all the way around so in a run of six consecutive outlets along a wall, none of them were on the same circuit.

After my folks passed on, I sold that place and moved into their house. One day I discovered there is only one single outlet circuit in the kitchen (not counting the fridge), so I can't run two high-draw appliances at the same time. Microwave running and want a slice of toast? Nope - "pop". Coffee brewing and want to make waffles for breakfast? Nope - "pop". Pick ONE.

 

I also discovered his small shop only has an 8 spot breaker box, and is wired with TWO 110v outlet circuits, two 110v light circuits (I'm a little baffled, as one would have worked fine in this little shop.), and two 220v outlets.

[Cypress Sun]

 

Maybe I'm the odd man out.  When I put in my workshop in an outside shed I ran the power to it myself.  I put a 100 amp breaker in the main box, buried a conduit and ran THWN in it with a 90 amp main breaker in the sub-panel.  I've got an RV out there so I put in a 50 amp circuit to it from the sub-panel.  I also put in an outlet for my welder, another for the air compressor, a couple of others for A/C, lights, and tools.  Before everyone says that it's overloaded, the RV never draws 50 amps even with all the A/C's running, the compressor is a smaller portable one.  I've never had a breaker trip or had any problems.  I've got nothing against electricians, I'm just cheap and willing to do the work to save $$.

 

Now the the criticism begin.   

 

Doesn't sound overloaded to me, assuming you put 3 - #4's and a #8 copper wire in the conduit. I'm a little puzzled as to the 90 amp breaker for the main in the shed but that's fine for a disconnecting means. This is also assuming that your main panel is able to accommodate the additional load. I hope that you separated the neutrals and grounds in the shed panel by floating the neutral bar w/separate ground bar and ran a 4 - wire to the RV with the proper receptacle. Air compressors and welders are an intermittent load although the code has certain load factors for motor and welder applications. Believe or not, a 100 amp service is fine for a smaller residential house up to about 1,500 square feet depending upon how many ac/heat systems in the house.

 

Usually cheap and "handy man" type electrical work is not a good idea. Normally, electrical work is best left to a competent electrician. Improperly done plumbing or ac will just leak water or air....improperly installed electric wiring can/will burn your house or business down.

 

You'll get no criticism from me, I don't live there and didn't install it......admonishment perhaps, but not criticism. 

 

YMMV