# Is this diagram for 220VAC outlet correct?

Joined Jul 18, 2013
22,855
Foreign language to me. What gauge wire for 20 amp service and what gauge for 30 amp? Would 30A be 10 gauge?
NEMA 6-30, Look at the socket examples posted by Bertus.
10ga For 30amp, 12ga for 20amp.
Max.

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#### MisterBill2

Joined Jan 23, 2018
8,457
One thing not mentioned is wire colors. I have seen some real excitment when a white wire was the other side of a 240 volt circuit. So when I put a 240 volt circuit in I color that second side red with a permanent felt marker on both ends. Then nobody will confuse it with a neutral. and in some of our areas here it is 230 volts, not 220 or 240. Go figure on that one. I find it always good to bring the neutral along to the box because then I can split an outlet by removing the hot side jumper and have two separate 120 volt circuits, if the need arises. And then the second side feed can be the red wire.

Joined Jul 18, 2013
22,855
From what I know of US power distribution, there was a general agreement or stipulation that all areas or the US would conform to 120/240 following a period after WWII.
In Canada, all provinces are 120/240.
I prefer to use coloured electrical tape at all termination points to mark any conductor that is used as a substitute for the proper colour.
In the case of a dedicated circuit as per the OP's table saw, it would be wiser to provide the dedicated 240v circuit without neutral, if not needed for the equipment it is feeding.
Also cheaper on cable, if it happens to be a lengthy run!
Max.

#### MisterBill2

Joined Jan 23, 2018
8,457
From what I know of US power distribution, there was a general agreement or stipulation that all areas or the US would conform to 120/240 following a period after WWII.
In Canada, all provinces are 120/240.
I prefer to use coloured electrical tape at all termination points to mark any conductor that is used as a substitute for the proper colour.
In the case of a dedicated circuit as per the OP's table saw, it would be wiser to provide the dedicated 240v circuit without neutral, if not needed for the equipment it is feeding.
Also cheaper on cable, if it happens to be a lengthy run!
Max.
CHEAPER is not always the best option. Bringing a neutral along will allow powering accessory items from the same feed. then suddenly it is less costly than runniong a second circuit for the accessory items. Been there, done that, got the diploma too.

Joined Jul 18, 2013
22,855
got the diploma too.
Good for you!

I always believe in high current 240v devices especially, deserve their own circuit.
My Stove, My HVAC, my Garage Furnace, My welder, my power saw, etc, etc.
Low power items are generally 120v, and can be accommodated from a 120v duplex plug.
Max.

#### MisterBill2

Joined Jan 23, 2018
8,457
Good for you!

I always believe in high current 240v devices especially, deserve their own circuit.
My Stove, My HVAC, my Garage Furnace, My welder, my power saw, etc, etc.
Low power items are generally 120v, and can be accommodated from a 120v duplex plug.
Max.
Most stoves also include a few items, such as oven lights, top lights, solenoid valves, and clock timers. Often those items are powered between one line and neutral. So the neutral connection for a stove is important. even more on my HVAC system the blower motor runs on 120 volts as does the primary of the 24 volt transformer. The outside unit does run on 240.
And one company, where I installed a robot with a system, had a delay of a few days and a much higher installation cost because they did not have a neutraal wire to that power drop. They had to get a 2 KVA transformer and a disconnect breaker box to provide the 120 volts that their lack of a neutral did not provide.

Joined Jul 18, 2013
22,855
My HVAC AC system is only 240v no neut!
The items I listed previously do not require any 120v circuit, if it were necessary I prefer to have 120v ancillary equipment on a local 15a circuit rather the a 30a breaker.
Industrial equipment is quite a different thing.
Max.

#### Tonyr1084

Joined Sep 24, 2015
5,862
cheaper on cable, if it happens to be a lengthy run!
The run length would be approximately 30 feet; and the outlet is going to be in the floor by the foot of the saw. Between the saw and the work table is where the plug will be, so I won't be tripping over a cord. Running a neutral may make 120V available at the work table for small hand held equipment like routers and sanders (etc). Also there will be a dust collection tube at the same location to extract sawdust. The dust collector will be in the far corner and will be powered by 110 (120) VAC. Other equipment will also be 110V. Only the table saw will be 220V.

Funny thing about equipment and their voltage requirements - - - light bulbs (incandescent type) which were rated for long life were measured and calculated from an odd voltage. Memory doesn't serve me well on this but I think that a 5 year INC bulb was rated at 106VAC, not 110VAC. Odd voltage requirements like 230V may be what makes the statement legal that there's X amount of power developed by the equipment such as a table saw. I believe it's a way to make a legal statement; like an advertisement I recall for a certain cell phone company who stated "Nobody has a more powerful network." Which is 100% true. The consumer is left to imagine that their network is the most powerful. But that's not what they said. They said 'The FCC has limited all cell phone carriers to a specific amount of power (in transmitted wattage) and nobody has a more powerful network.' If you make a table saw that has 2 horse power and I make virtually the same saw but advertise mine as being 2 and 1/8 HP it may be because I'm rating my equipment at a slightly higher voltage. The end user will only have a set amount of electrical power (voltage and amperage), so both our products will perform the same. But because mine is rated slightly higher it might be more appealing. And I might even be able to get away with charging a slightly higher price for it.

#### MisterBill2

Joined Jan 23, 2018
8,457
OK, save a few pennies on the cable, then. My experience has been that sometimes the future is different from the past, and that occasionally folks change their minds. If for some reason the requirements change you would be ready.

Joined Jul 18, 2013
22,855
@Tonyr1084 The problem with taking a 120v outlet from one 240v side and neutral where 10g wiring and a 30a breaker is used, and you wire the outlet up using 14g, doing this is you most likely will contravine the code as it states you cannot use a smaller conductor that has a llesser rating than the breaker rating.
You should confirm this with your local service provider first.
Max.

#### Tonyr1084

Joined Sep 24, 2015
5,862
@Tonyr1084 The problem with taking a 120v outlet from one 240v side and neutral where 10g wiring and a 30a breaker is used, and you wire the outlet up using 14g, doing this is you most likely will contravine the code as it states you cannot use a smaller conductor that has a llesser rating than the breaker rating.
Yes, I'm aware of that. But if I use 20A I can continue to a 20A standard 120V outlet with 12 gauge wire without violating code.

I had an electric stove with 10 (or maybe 8) gauge 30A (or maybe 50A) wiring. Repurposed those wires for 120VAC with a 20A breaker on each leg. One leg powers the range that's there now and the other leg powers one outlet and the microwave oven over the stove. Even though the wire can carry more current, I'm limiting it to the additional 12 gauge wires I've run at 20A. I don't think the code says you can't use 10 gauge on a 20A breaker; though it wouldn't be cost effective. However it is greatly effective to not have to cut open the wall and pull the heavier wire out only to replace it with smaller (12 gauge) wire.

#### shortbus

Joined Sep 30, 2009
8,470
the outlet is going to be in the floor by the foot of the saw.
I'd rethink that one. If the saw is ever unplugged and wood working is still being done saw dust will get into the outlet. And I've found saw dust in some places I never thought it could get into over the years. And if there is ever a spill of water or broken pipe in the room, even with the saw plugged in it could be dangerous to you.

Joined Jul 18, 2013
22,855
I'd rethink that one. If the saw is ever unplugged and wood working is still being done saw dust will get into the outlet. And I've found saw dust in some places I never thought it could get into over the years.
I have used the surface mount outlet boxes with lids that snap shut when not in use for very dusty environments etc, but they don't prevent water entry however.
Max.

#### shortbus

Joined Sep 30, 2009
8,470
Surface mount? Or as I took Tony meaning in the floor. When I see *surface mount* I imagine like a normal old type behind the stove outlet, like I use for my welders and on the end of the extension cord for them.

#### KeepItSimpleStupid

Joined Mar 4, 2014
4,663
Get yourself a sawatop. www.sawstop.com. it won;t cut a finger, wet wood or a hot dog with disablig the safety. It will cost you \$100.00 unstead of finger. Never used one, saw one at the local woodcraft store.

Wire does depend on length (2x length), voltage drop and I think FLA for motors. No more than 4% voltage drop. Wiring should be <=80% the breaker rating.

Joined Jan 15, 2015
5,916
Yes, 20 amp service would be 12 gauge AWG 12 and 30 amp service would be 10 gauge AWG 10 for average residential use of average run length. Just as a rough example if I am going to run 30 amp or 20 amp service using AWG 10 or 12 respectively if the distance exceeds about 60 feet I would consider going from AWG 12 to AWG 10 for 20 amp service and AWG 10 to AWG 8 for 30 amp service. Really, all things considered the cost differential is not that great.

Ron

#### Tonyr1084

Joined Sep 24, 2015
5,862
or broken pipe in the room,
No water in the room. Maybe a water bottle at my desk, but that's a linear distance of close to 30 feet.
if the distance exceeds about 60 feet
Expect the run to be not more than 30 feet.

Joined Jan 15, 2015
5,916
No water in the room. Maybe a water bottle at my desk, but that's a linear distance of close to 30 feet.
Expect the run to be not more than 30 feet.
Then I would use AWG 10 for 30 amp service. Matter of fact for shop use I would use AWG 10 / 3 Romex or similar where allowable and BX cable where the cable run can't be exposed. I see where this began with plugs and sockets and if it were me I would likely opt for a twist lock rather than standard blade type plug and socket. They are as easily had at home improvement stores as the standard blade types. Really your call. BX is also called Armorlite which is just a brand name.

Ron

#### KeepItSimpleStupid

Joined Mar 4, 2014
4,663
Tony:

This is a garage, so is a sub-panel in order or even two.

One is a safety issue where you have lighting on two separate circuits.

The second is also a safety issue.

When the machinists at work designed their shop, they wanted the breaker panel in the shop for good reasons.

High school shop definately had an emergency stop. I don't remember how power was enabled, but anyway, when the instructor left, he just hit the emergency off as he went out the door. This kept all of the mchines OFF.

So, pretend you have infinate money and infinae resources and figure out what you might like. The NEC hates unconnected wires.

But let's say you want a better dust collector.

They usually stay on for a few minutes as you move from machine to machine.

You also might have a keyfob version or an outlet that keeps the vacuum system on.

It can open/close the gates near the machines.

We had a few interesting things in our shop:

A Neidermeyer flex exhaust fan with a light primarily for the welding area and for painting.. It was really nice.

We made our own paint booth. Simple and effective. it was a blower similar to a furnace blower but tiny.
The booth (about 2'h x 3' w 2.5'L with a hinged and chain, so it would be straight when open.
The back of the booth had a furnace filter and the blower pulled paint laden air through the filter.
Then, the Neidermeyer exhausted it. Just the ability to pipe it outside could be useful to you.

We had an auto-rolling cord on a swivel. You might consider 2. One for a hand power tool and the other for a light. The power was above a table. The cord of the hand tools never got in the way.

Don't forget air. We had air everywhere. Near the mill and lathe for dusting off, on the benched
Air was either secured on the wall or it dropped from the ceiling. You might use an air sander, file or whatever. 3/4 silver soldered copper made up the air lines with quick couplers that shut off the air supply when something was removed.

You do need a drain or preferrably an auto-drain that lets the water out automatically.

The air was de-humidified.

We generally didn't need a filter or mister in the shop. We did individually for machines 100 foot away.

At home, I have to fix what we had. the tank is tiny. No automatic switch. The compressor was from a beer tap, I think. It's currently seized.

I was able to fill a C02 cylinder with air and I used a double male. When the bottle was full, the bottle valve was shut off and the compressor turned off. There was a rupture disc on the C02 tank. I got it from a junkyard some 50 years ago. The compressor had a valve and pressure that could be opened to vent the system safely.

Not everybody has a "dust collection" to show off.

It's also nice to use a main breaker panel. With the right panel, you can get breakers that can be remote tripped.

To use a main breaker panel as a "main lug panel", you generally need to buy a ground bar kit. This gives you grounds for the panel. There is usually a way to remove the ground-neutral bond in the panel,so you can keep G-N-L1-L2 separate.

If the structure is attached, you don't need a ground rod.

Incidently, you CAN use a 200 A panel and feed it with a 60A service. As long as the feed is fused at 60A, you can use the 200A breaker as a switch.

Reminder:
Run L-N-G and N to the switches and to the lamps. You can add automation stuff later which requires a neutral at the switch.