View Full Version : Okay - 15Amp or 20 Amp Outlets?
05-04-2001, 07:50 AM
Thanks to all that answered about quad or double outlets. I will do a combo of both depending on the location.
But the next question (that i forgot to ask before) is what amp outlets? 15 or 20? Or should it be a combo for different machines?
So far I have a router, router table and miter saw for stationary tools not to mention various hand tools (scroll saw, drills, and circular saw). Pricing out drill presses (standing or table top), dust collection (Grizzly 1 1/2 hp or 2 hp not much price difference - 220 volt?), and table(cabinet) saw (Grizzly 220 volt).
05-04-2001, 08:19 AM
Go with the 20 amp outlets. That way you shouldn't ever be "wanting" for amps on any of your 120V tools. Of course a separate 240V line is in order for the Dust Collector and the Table Saw.
05-04-2001, 08:23 AM
By the way, I think that you mean breakers. The outlets should be the "standard" household outlets.
05-04-2001, 08:38 AM
I mean the outlets - I can get a box of 15 amp outlets at Home Depot but have to purchase the 20 amp individualy.
I will have a 20amp Circuit Braker in the panel - one for each wall for a total of 3 breakers. The difference is that fact that I have to spend more money on the outlets if I have to purchase seperatly instead of a box. But its only money.....
05-04-2001, 08:49 AM
Breakers, outlets, and wire need to be sized correctly. 20Amp 110V outlets are different than 15amp outlets and will accept 20Amp and 15amp plugs (which are very different).
05-04-2001, 11:22 AM
As STeve stated make everything match up 20 amp breakers ,20amp rated receptacles and #12 wire you won't be sorry u spent a little more today to circumvent those nuisance trips of the breakers in the future.
05-04-2001, 12:35 PM
Dick is so right.
The cost of the Outlets is something that I never worry about. The comercial outlets are designed to be used. The box of ten outlets you find at hd for a low price is designed to have a light pluged in and left for 5 years until your wife decides she wants to redecorate. The comercial outlets hold up to the kind of abuse we put things through in the shop.
The other thing. You have three 20 circuits, don't wire one per wall. I would interleave them on all three walls. It will cost you a bit more for wireing now, but in the long run it will save you lots. Assume that the three circuits are A, B and C. You want to go down each wall in ABCABCABC. That way you won't tend to have too many tools on one circuit.
You also want ot dedicate a circuit to each of your large tools. Table saw, Dust Collector, Jointer, Planer. ect. Now it the time to get these wired, it is much harder later.
05-04-2001, 11:19 PM
May I make a suggestion? I'd go with the mixing the circuits, ala ABCABCABC, but as well, I would mark the recepticles (color code?) to make it easier to balance your load when running multiple devices.
05-05-2001, 12:08 AM
HD has some really neat 20 amp outlets for shop use. They are grey in color and made of nylon. After about 30 years I had to replace some of my bench outlets and used these. You can't break these outlets like you can break the plastic ones and they really grip the plugs so much better. HD also carries the grey nylon cover plates too. Spend the extra $20-$30! You'll be glad that you did.
Once again I find myself the odd man out.
I would suggest 15A system. Odds are your not going to be using
more than one power tool at a time except perhaps a lamp or shopvac as a DC. If your popping a 15amp breaker reasses what your doing. The bigger stationary tools should be on their own 15A leg, I've yet to use my portable planer and oh say my RA at the same time. If a tool can be converted to 220 do it its not cheaper per amp\hr but is better for the tool and may enhance its performance.
Also consider the addition of a few switch operated outlets, be nice if say you could flip a swith for the shopvac\DC to come on.
05-07-2001, 01:17 PM
Rewiring is a pain. I suggest that inwall wiring should be 12GA or 10GA. The reason is this, 12GA (20Amp), 10GA (30Amp) can be used now for 110V devices. Later you may want to switch some of those devices to 220V and the wiring will be able to accomidate them, the only changes being the breaker and the recepticle: no tearing through the walls. The other way is to run most of your wiring in coduit surface mounted on the walls. If you need to change wiring you can pull new wiring through. Just make sure to use large conduit. The suggestion for skip wiring circuits down the wall is a good one, although you'll need to plan your wiring runs approprately. Also don't forget to install some outlets in the ceiling. Ceiling mounted powercords are great. When installing wall boxes use the largest and deepest ones you can. If you properly wire your circuits (i.e. using pigttails) you'll have lots of wire to store in your boxes. Finally, think about using a couple of sub panels to control your tools. For example the main panel (or main sub panel in your shop) should have the lights, emergency lighting, and a couple of 110V circuits on it. You should then have a subpanel for your machine circuits (table saw, dust collector, air compressor, jointer, powerstrips for hand tools, etc). Now lets say you turn a bunch of tools on and trip the subpanel breaker. At least you will still have your lights on so you won't be working on a table saw in the dark.
Just something to think about. BTW, if your building a shop the cost of the wiring, breakers, panels, switches, light fixtures, outlets, etc. are a part of the building cost and will reduce the amount of capital gains when you go to sell. So it doesn't make a lot of sense to fuss over the cost of these fixed items.
05-07-2001, 02:06 PM
Update - I went to home depot and got the stuff as follows:
1)You can only get industrial/commercial 20amp outlets. So I got soem need a couple more so I'll leave wire in the boxes to complete.
2)I got the 20 amp circuit breaker for the sub panel.
3)I got all the plastic outlet boxes (nail into wall with provided nails) easy and simple! I like that.
4)Got 12/3 wire 250'. Should be plenty.
5)I even got a couple of double boxes for the corners.
I also finished framing the garage! It is level - bubble in the middle or close to it.
I am going to measure the lowest part of all and measure from ceiling to that level (50" aff) and make all locations from this reference point. Nail boxes into place. Since I made my walls with 2x3 instead of 2x4 since my walls are out of square I have room to run all wiring behind the studs and into the boxes. No drilling required!
Now if I only had the time to complete it....
Thanks for all your help in responding.
05-07-2001, 03:30 PM
Hope the breaker you got was GFI. Is code in most places that you must use a GFI when the floor is conc.
Steve Wilson (Guest)
05-08-2001, 02:05 PM
CGI breakers are expensive. You can still meet code by having a CGI outlet as the first outlet in a run. So wire from breaker to CGI outlet. Series connect from the CGI outlet to the next outlet. Wire the remaining outlet's in parallel (i.e. use pigtails).
05-09-2001, 09:24 AM
Why CGI? What is it? And my floor is concrete.
I live in NJ and should I call the electrical inspector and ask him?
05-09-2001, 09:44 AM
I think CGI is a variant on GFI - Ground Fault Interrupter. You must have these in garage and other wet locations by code. This includes kitchens, bathrooms, and outside outlets.
One GFI breaker can cover an entire string, but in shop situations where you are going to have several circuits you'll probably wind up with several GFI's.
Yes, they are more expensive than standard breakers, but not prohibitively so.
If you call the local code inspector you'll need to be sure you have a building permit.
Steve Wilson (Guest)
05-09-2001, 01:10 PM
Good catch! It is GFI. I was doing some web work when I posted and had cgi on my mind. So yes GFI. As to cost IIRC they started at >$20 for a 15amp breaker and went up very quickly from there. YMMV as the cost is dependent on the brand of panel you have. A GFI receptical is on the order of $5. Basically, if you shop is a garage it needs GFI to be code compliant.
05-12-2001, 02:01 PM
I would suggest no circuit smaller than 20AMP, except for lighting. You never know what you may have to plug into an outlet. For instance my circular saw pulls 15AMP.