Another Shop Wiring

[rh111]

Though I am not a BT3'r, I greatly appreciate this forum as I have learned a ton of useful information here.

I moved into a house last year that has 2 outlets in the garage. Those 2 outlets are a mere 15 amp circut. If I do heavy cutting with the TS, I trip the circut. My old house has 3 20 amp circuts in the garage and never had an issue. I have put together a quick scetch that I might get insight from the members on. All of my tools are 110v. The Delta contractor saw, shop vacs, router, miter saw, and varied hand power tools is what I have.

I appreciate any thoughts, suggestions, comments that anyone can provide. I have been thinking about this for a couple of weeks, and have made more revision than I care to list or remember.

[Uncle Cracker]

OK, here's a couple of suggestions to get the ball rolling... First, let me say that, without knowing how your tools will be arranged, or whether you will be using all of your bays for car parking or just some, then my suggestions will be general in nature.

Try to have at least two 20A circuits dedicated to tool usage, and keep tools that might be used in tandem (such as a table saw and dust collector) on different circuits from each other. Also, try to keep your lights on a circuit that is different from your two tool circuits.

If you will have big tools in the middle of the floor, consider making a #12 or higher grounded extension cord to run from your wall outlets to the center of the floor, without a whole lot of extra length to coil up and trip you or burn off precious volts. Put a fat 2-gang outlet box on the end of it, with two duplex outlets in it.

Use the ceiling outlet (which I presume is for the door opener) as a source for a ceiling-hung air filter, and for a good retractable extension cord setup.

Don't put outlets where you will not be readily able to get to them (like under a bench or behind a shelf unit.

Don't cut corners. Always err to the safe side, particularly if you only want to do this once...

Have fun...

[rh111]

I guess I should premise my earlier post with a few things. The double door area is where the cars are. Most everything that I own of a larger nature is mobile with the exception of the work bench. The garage door opener outlets are not shown in the diagram. The ceiling outlet in the diagram is with the intenion of building/buying an air filter to keep the dust down leading into the house. Currently own no machines requiring 220.

[LCHIEN]

if you're going to be halfway serious, you'll want these tools, each of which will prbably want to have its own circuit:
Air compressor
Dust collector
Table saw
Air conditioning and or heating (optional)

In those cases, except for running clocks and other small appliances, its not really much use to put bunch of outlets on the same circuit - just encourages other things to try and use these already heavily loaded lines. Unless you plan to move those items around a lot, just put one duplex outlet on each circuit near the intended point of use.

Now you could put other tools on the same line with the table saw, this would be OK if you are the sole worker and only will have one tool on at a time. BUT if you ever will have your son, wife, BIL, FIL working in the shop with you, maybe planing while you are ripping, then you might want to have at least two circuits for heavier tools.

finally another circuit for lights, radio, chargers, refrigerator, air cleaner, shop vac other essential relatively low amp items.

I found an overhead socket for my TS and some other heavy tools with a drop down 12Ga cord and a hangar to relieve the tension on the plug was helpful in removing trip-over extension cords and cleaning up the floor.

Also, placing the outlets along the wall, positioning them up from the ground is quite useful, not the 12-18" you find in the house for aesthetic reasons but maybe 36"-40" will get them above worktables surfaces and also save your back from bending over all the time regarddless of whether theres a table there or not.

anyway those are some of the things I learned/thought about.

P.S. check the existing wiring in the garage - if its 12-2 then you can probably change the breakers to 20A. But, if its 14-2, no can do. Should be imprinted on the wiring jacket.

P.P.S. re: GFCI - I would not be real sure about applying GFCI protected circuits within the garage shop. One question is why - usually GFCI recommended for wet areas or areas where you might otherwise come in contact with an alternative ground (to the wire ground), e.g. the ground fault, while touching exposed wiring (Usually as the result of a second fault). I don't think this is likely to happen in the garage. Second is that some GFCI are notorious for tripping while connected to high motor power loads. Might be more trouble than safety.
If one of your circuits goes to an outside outlet, then perhaps you should put a GFCI at the point where it leaves the interior of the garage.

[Uncle Cracker]

Currently own no machines requiring 220.

Think now about the future. If this will be an easy add later, then don't worry about it, but while you are running wires and fishing walls, you may want to make it easy on yourself.

[LCHIEN]

Think now about the future. If this will be an easy add later, then don't worry about it, but while you are running wires and fishing walls, you may want to make it easy on yourself.

If you follow my advice and only put a single outlet where a heavy tool is located, it will be easy enough to change this one outlet from 120V to 220V in the future. (change the breaker to a 2-pole breaker, move two wires in the breaker box and change the one outlet).

[rnelson0]

finally another circuit for lights, radio, chargers, refrigerator, air cleaner, shop vac other essential relatively low amp items.

A fridge isn't necessarily a low-amp item, especially if it has a freezer bay. The running load may only be a few amps, but if the compressor kicks on it might jump above 10 amps - which would probably kill even a 20A circuit if a tool is running on it. Refridgerators and freezers should always be on their own circuit.



The plan looks good. I assume you are leaving the original outlets, which are great for portable lights, a stereo, etc. Location is all you - as I said in my other post, lay out the shop THEN the electrical. I did it the other way around and now my workbench is covering an outlet by all of two inches. Moving the outlet now is a huge pain in the ass, but if I had built my workbench first, I'd have figured out where to put it initially, when it was easy to move. Oh well.

[LCHIEN]

A fridge isn't necessarily a low-amp item, especially if it has a freezer bay. The running load may only be a few amps, but if the compressor kicks on it might jump above 10 amps - which would probably kill even a 20A circuit if a tool is running on it. Refridgerators and freezers should always be on their own circuit.

.

for the purpose of planning a shop they only take a few amps. All motor devices have large surges which breakers are designed to ignore. So even if the breaker is carrying 10 amps continuous, and the fridge compressor kicks in and draws 20 amps for a second, the 15A or 20A breaker should never trip. (Do a search here for my post on "Circuit breaker tutorial")
Now, freezers should probably be on their own breaker for another reason: If something else on the line trips the breaker then you can lose hundreds of dollars in frozen goods. You don't want the freezer to be at the mercy of another tool or appliance.

[JimD]

For the tools, all you really need is one 20A circuit for a one person shop. DC should be on a different circuit, however, so that's two. Depending on your DC, lights might be able to go on the same circuit as the DC. Mine is 1hp so I do that. 3 is the most I see (two 20A with one being for the DC or possibly some handtools that will not involve the DC and a 15A for lighs). The only advantage I see to more circuits is if you need them to meet code (unlikely but possible if you put enough on one wall or something) or if you want to always have a good circuit if you trip one. My box is in the next room from the shop so resetting is not big deal and I've never had to.

I would add no more than 3 but make sure you can get a 20A circuit next to any large tool that needs it. For garages, you need GFCI but that is just one special outlet at the start of the circuit.

Jim

[Black wallnut]

With the assumption that is easier to do it the first time........ Space outlets every 3 to 4 feet along each wall. You never know what projects/ tools you will be using in a few years. It is nice to have plenty of options for final sanding for larger projects. If you are tall enough to reach ceiling outlets are really handy!