Yet another electrical question

[Anthony Whitesell]

I'm pondering the purchase of a bandsaw and one of the options is a Grizzly G0513X2 which is rated at 20/10 amps 110/220VAC.

220VAC is not an option for me (not room in the box), so I am stuck with 20amps on 110VAC.

I know:
15 amp breaker - 14 gauge wire
20 amp breaker - 12 gauge wire

I don't know:
25 amp breaker - x? gauge wire
30 amp breaker - y? gauge wire

and
What size breaker do you recommend for the bandsaw which is listed at 20 amps on 110 VAC?

[David G Baker]

25 amp breaker-10 gauge wire (never seen a 25 amp breaker)
30 amp breaker- 10 gauge wire
The wire for your Grizzly
110 volts 20 amps- I would go with 10 gauge wire if the unit actually uses 20 amps at any point.
220 volts 10 amps- I would go with 12 gauge wire if for no other reason than I never use 14 gauge wire for anything other than an occasional ground wire.
Others may disagree with what I would do but I always error on the safe side.
The size wire may change depending on how far the wire runs from the source.

[Ken Fitzgerald]

Anthony,

I downloaded the owners manual for the G0513x2 and Grizzly on page 24 recommends a 30 amp breaker at 110vac.

[Anthony Whitesell]

Thanks David and Ken. I didn't even think to try to download the manual. Now I have to decide: 1. Tear out the 12 gauge and install 10 gauge, 2. Use my last slot and run 10 gauge, 3. Drop the crazy idea of a 17" 400 pound bandsaw and stick with a 14" saw.

[Ken Fitzgerald]

Let us know if it 's #1 or #2,,,,:rolleyes:

[Anthony Whitesell]

That's funny! I'll let you know. The day it arrives will be nice either way.

There is a whole other aspect to the bandsaw purchase...space. The woodshop needs to expand to have a place to use the bandsaw (which ever one it is). The current shop is 8x12 with a 3x3 closet type area. The area is currently accomodating a 2 door ways, a 6'x2' bench, 4' wide TS, and a 3'x2' router table cabinet. The DC is in the "outdoor equipment area". I'm building a covered area outside for the outdoor equipment that can't be bothered by the squirrels (snowblower, lawn mower but not the bagger). Once the woodshop takes over that area, I'll need to wire in atleast one outlet for the bandsaw, drum sander, and planer. Since I have to mess with the wiring anyway...

[Peter Quadarella]

If you have another slot, you could pull out a 110v and replace it with a 220v, if you are messing with the electric anyway. Also, I would be surprised if your box has no breakers that could be combined to make room. When I did some testing on mine I found a few breakers that were servicing a single bulb each :confused:.

The extra work on the box would be offset by not having to rewire the bandsaw, and also save you having to use 10ga (with 220v, a 20amp/12gauge setup would be good).

[Tom Veatch]

...
220VAC is not an option for me (not room in the box), so I am stuck with 20amps on 110VAC...

Don't know the "proper" name for them, but perhaps you could use one of those half-height breakers that contain two breakers in a single slot to replace a couple of existing 120v breakers. My service entrance panel has a number of those installed.

That would free one slot which with the existing empty slot would give you the space for a 240v breaker.

[Jim Becker]

The cost for you to install the higher amperage 120v circuit is going to be nearly the same as installing a 240v circuit, not including a few of the compact breakers that were mentioned. But you should consult a licensed electrician to be sure doing either will not over load your breaker box since it's already so full.

[Anthony Whitesell]

Consult complete. Although the panel is full of breakers, many of the breakers are low count and/or low usage circuits; including two circuits that have 1/2 of the shop lights (6 duplex 4' flourescent fixtures) and the other has the air compressor. So I can either move the lights to another circuit or add a tandem for those two circuits.

I am leaning towards the 220VAC for future expansion (ie., 8" jointer), which leads me to my next questions: Can 220V outlets be wired like 110V outlets with multiple outlets on one circuit? I would think the same gauge-amperage rules apply (14ga-15A, 12ga-20A), correct?

[Tom Veatch]

...Can 220V outlets be wired like 110V outlets with multiple outlets on one circuit? I would think the same gauge-amperage rules apply (14ga-15A, 12ga-20A), correct?

Yes, and Yes.

Wire gauge is determined by amperage in the usual case, but for very long wire runs, excessive voltage drop may require increasing the wire size. There is no requirement to increase the wire gauge in a given circuit simply because it's 240v instead of 120v.

I've heard tales of some jursidictions/code enforcement officials limiting 240v circuits to single outlets, but if so, that's a restriction that is neither universal nor justified by the physics of electricity. My shop is wired throughout with 240v circuits, each of which has multiple outlets. Some of the circuits are wired with /3 cable (3 conductor + ground) and the outlets on those circuits are dual-voltage. They look like a regular duplex receptacle except each contains one 120v and one 240v outlet.

[Anthony Whitesell]

I've done lots of eletrical wiring, but nothing that has involved installing 220V breaker, line and outlet.

I know I should have asked this along with the other questions. 220V uses (12) /3 wire, which has Red, Black, White, and Bare. White=neutral, Bare=Ground, Red and Black are Hot. Does it matter which side of the breaker or outlet the Red and Black are connected to?

[Tom Veatch]

I've done lots of eletrical wiring, but nothing that has involved installing 220V breaker, line and outlet.

I know I should have asked this along with the other questions. 220V uses (12) /3 wire, which has Red, Black, White, and Bare. White=neutral, Bare=Ground, Red and Black are Hot. Does it matter which side of the breaker or outlet the Red and Black are connected to?

The only time you need /3 cable is if the circuit is required to provide 120 and well as 240 volts. If you are wiring a straight 240 branch circuit all you need is /2 cable (2 conductor + ground, black, white, and bare). 240 volts doesn't use a neutral conductor. You wire it just like a 120 volt circuit except at the breaker box, the white wire goes to one of the breakers in the common trip set, and the black wire goes to the other. The bare wire goes to the ground bus the same as in a 120v circuit.

At the receptacle end of the circuit, the bare goes to the ground connection and the the black and white wires are to the blade connections. The difference is that, unlike a 120v circuit, both wires are hot relative to ground so it doesn't matter which blade which wire is connected to. The white wire should be marked with tape or heat shrink tubing at each connection on both ends.

Some 240v circuits do require /3 cable (3 conductor + ground, red, black, white, and bare). But that is only required where the applicance requires a 120v as well as 240v supply. Examples would include ranges, dryers, etc. I know of no woodworking tools that require /3 cable wiring.

I used the /3 cable in my 240v branch circuits only because I used dual voltage outlets and wanted both 120 and 240v available at each outlet. Those circuit that are straight 240v are wired with /2 cable. The wiring was done by a licensed electrical contractor under permit and inspected and accepted by the local code enforcement officials. So I have no doubt it was done in accordance with code requirements.

[Anthony Whitesell]

I'm liking this. I have a whole bunch of 12/2 wire left from the last project. IIRC, 100 feet was $74 and 250 feet was $83. So I bought 250 feet.

What is the purpose of the heat shrink tubing on the white wire? Is it just to note that is also hot?

P.S. Thank you all for your time.

[Peter Quadarella]

Anthony, I know this is a little off track of what you were originally thinking, but I think you are doing the right thing and you will be glad for it down the road.

If you could do two 220V circuits, that would be even better as it would open the door for more powerful dust collection down the road, and it's likely you'll never need any more than 2.

Yes, I believe that's a standard way to mark the white wire as hot (but hopefully someone more experienced will chime in and agree :) ).

[Anthony Whitesell]

That's a thought Peter but I don't think it will fly in this house. There is only a 100 amp service in a 20 slot box. Wellx2, Dryerx2, Stovex2, Clothes Washer, Bedroomx3, Outside Outlets, Kitchen/Bath, Fridge, Microwave/AC, Furnace, Living Room, Workshop, Workshop Lights, Air Compressor. 19 out of 20. :eek:

To add another 220 circuit, I have two options; 1. move the workshop lights to the same circuit as the room above (the laundry room lights are on the living room circuit from above); 2. move the two of the following Air Compressor, Workshop lights, or Microwave/AC to a tandem breaker. :confused:

I'm think I like #1 best. Least likely to "upset" any one by having 21 breakers in a 20 breaker box. :rolleyes:

I know I'm taxing my current DC, but I need to take one step at a time. I'm probably not far off from needing a larger DC, or atleast one with more chip capacity anyway. I need to save something to do later.

[Rob Russell]

It is a requirement to "reidentify" neutral conductors as being hot.

An option to provide more breaker slots would be a subpanel. You could take 2 slots and install a 60 amp subpanel. That would give you enough juice to run what you want in the shop and would give you a bunch more open slots to work with.

Yuo could relocate the compressor circuit to the subpanel.

[Tom Veatch]

...What is the purpose of the heat shrink tubing on the white wire? Is it just to note that is also hot?
...


Correct.

Normally, white wires are reserved for neutral conductors which are bonded to ground potential at the main panel. When a white wire is used for another purpose, such as a hot lead in a 240v circuit, it must be reidentifed by marking to show anyone opening the enclosure that it is not a neutral wire.

Of course, prudence dictates that one verify the state of all accessible wires irrespective of color codes.

[David G Baker]

I agree with Rob on installing a sub panel. It will make things much easier in the future by making a lot of room for electrical expansion. I have at least 5 sub panels between my house basement and my two out buildings. 60 amp panels go on sale frequently and many times have the breakers included.
I use black felt pens to mark the white wires as a hot leg or if I have shrink tubing available I use either red or black shrink tubing.

[Anthony Whitesell]

I thought of that as well, but I think I'll keep that for the next 'upgrade'. Although I was reassured by two different electricians that it would be find, somehow I'm a little nervous added a 60 amp sub to a 100 amp main. Something just doesn't compute, but that could be because I'm an EE.

If I find the space and $$$ for a higher HP DC system it will have to be 220V, in which case I'll add a subpanel and move all the shop breakers into it.

Thank you all for your help. Now I have to decide on the bandsaw and pull the trigger.

[Rob Russell]

FYI, adding a subpanel just gives you more breakers. It doesn't really increase the load on the main panelboard beyond the fact that you can run more circuits. If you jammed a bunch of the half-height breakers into your main panelboard to free up space and ran all hte new circuits you want - you're accomplishing the same thing.

Your main breaker is 100 amps. Once you exceed that total amount of current draw, your main breaker trips.

I'd rethink the subpanel. It's basically just adding in a big 4-wire 240v circuit that terminates in a panelboard instead of a junction box with a receptacle.

[John Eaton]

I agree with with the sub-panel ideal. It would forstall issues wiring larger machines in the future (and you know you'll get more).

-- John

[Anthony Whitesell]

I think the only thing left would be a larger DC which would require it's own 220V circuit. I still need to acquire a SCMS (120V) and a jointer (probably 220V, especially if I run a 220V Circuit:D).

Being that I'm only one person, I can only run the DC and one machine at a time. As long as I have one circuit for the DC and one for the tools (or perhaps 1 110V and 1 220V), that's all I can use at once.

If and when the larger DC comes, then I will add the subpanel. No doubt about that. I'm just not really keen on allowing for enough breakers such that the load gets into the range of possibly tripping the main.

[Mike Wilkins]

Call me Mr. Overkill or anal. Your choice.
I used 12GA for all 110-120 circuits and 10GA for all 220-240 volt runs.
Used commercial-grade outlets and light switches all over. Commercial grade switches/outlets have more beef inside for heavier duty use, and just plain last longer. Especially in a shop environment.

[Rob Russell]

Being that I'm only one person, I can only run the DC and one machine at a time. As long as I have one circuit for the DC and one for the tools (or perhaps 1 110V and 1 220V), that's all I can use at once.

If and when the larger DC comes, then I will add the subpanel. No doubt about that. I'm just not really keen on allowing for enough breakers such that the load gets into the range of possibly tripping the main.

Adding up the value of all the breakers isn't what you'd worry about, it's the actual running loads that you'd need to worry about.

A subpanel would just make it easier to do the wiring because you'd ahve the space for extra 120v utility circuits in the shop.

As a 1-man shop, you're right about 1 machine + DC running, although the compressor can cycle on at the same time.

Your shop, your decision.

[Peter Quadarella]

By the way, I have a 30 amp sub-panel. Most people around here would tell you that is not nearly enough, but I have not had a problem running my 3HP jointer (or my 2HP BS) and my 2HP dust collector, along with my lights at the same time. I have two 20amp 220V circuits, along with a 15amp 110V and several 20amp 110V circuits in the 30amp sub-panel in my shop.

[Anthony Whitesell]

I'm still leaning towards the Grizzly G013X2. If I go this route, I will wire in a 12 ga 220V only run from a 220V 20A breaker to atleast two outlets (thinking 220V jointer down the line).

With the breaker and wiring is setup for 220V 20A with no 110V requirement, which plug/outlet would you select? I'm thinking of going with a L6-20, three prong twist lock rated 250V/20A.

On another note, is it my imagination or is this webpage incorrect: http://www.lowes.com/lowes/lkn?action=productDetail&productId=197469-334-L620P-L&lpage=none

[Tom Veatch]

...With the breaker and wiring is setup for 220V 20A with no 110V requirement, which plug/outlet would you select? I'm thinking of going with a L6-20, three prong twist lock rated 250V/20A.

Personal opinion, YMMV, but I don't like using locking plugs with wall outlets. I know, there's less chance of kicking the plug loose from the socket, but, if tripping over the power cord is possible, I'd much rather have the plug come loose than have me face down on the workshop floor. I would use a non-locking 6-20 which is usually significantly less expensive as well.

On another note, is it my imagination or is this webpage incorrect: http://www.lowes.com/lowes/lkn?action=productDetail&productId=197469-334-L620P-L&lpage=none

Not sure what you're referencing, but the picture seems to be of a 3 blade 6-20R. At first glance, the inward facing tab on the blade nearest the camera looks like a 4th blade on the far side of the plug, but that's just a trick of perspective.

[Anthony Whitesell]

I was looking for something blantantly obvious that it was a 220V outlet and not 110. Are the non-locking in the round configuration?


As for the webiste, the specs so the L6-20 as 30A 125V

L6-20 = 250V 20 Amps

L5-30 = 125V 30A.

Oops.

[Lee Chadwick]

Is your shop seperate from your house? If so, I would consider having a seperate panel and meter installed. It would still be included in your monthly house bill if you wanted, but this way there is no question about overloading the main. Or you could upgade the current panel with a bigger service ( way more expensive in the short run but will pay off later)

[Tom Veatch]

I was looking for something blantantly obvious that it was a 220V outlet and not 110. Are the non-locking in the round configuration?


As for the webiste, the specs so the L6-20 as 30A 125V

L6-20 = 250V 20 Amps

L5-30 = 125V 30A.

Oops.

125V/30A is definitely the wrong spec for a L6-20. As for the straight bladed NEMA 6-20 configuration, the plug could look just like the picture in the link except for the blade configuration, or not. Just depends on the manufacturer. The socket/receptacle can either be a single outlet or a duplex configuration with the same overall size as the 125V/20A NEMA 5-20. Some pictures here (http://www.levitonproducts.com/catalog/dept_id_971.htm).

[Anthony Whitesell]

I definately hear you about tripping over the cord, but I'm afraid that might not be obvious to someone else (or me down the line) that those outlets aren't 120V. With the round pin configuration, it would make someone think twice about what the plug is for.

What's your opinion on using a 30A dryer plug? Or something like this http://www.lowes.com/lowes/lkn?action=productDetail&productId=71242-334-S42-SP-L&lpage=none

It might be overkill on the specs, but it does lock.

[Anthony Whitesell]

My wood shop is part of my basement. Currently it occupies about 12x8 of a 26x40 walk-out basement. I'm in the process of building a covered area outside to evict the squirrel-proof lawn and garden equipment into. I have lots of squirrels, mice, bees, and spiders around so I have to because as to what is left outside.

The shop should be should be about 12x16 afterwards.

[Tom Veatch]

I definately hear you about tripping over the cord, but I'm afraid that might not be obvious to someone else (or me down the line) that those outlets aren't 120V. With the round pin configuration, it would make someone think twice about what the plug is for.

What's your opinion on using a 30A dryer plug? Or something like this http://www.lowes.com/lowes/lkn?action=productDetail&productId=71242-334-S42-SP-L&lpage=none

It might be overkill on the specs, but it does lock.

Someone else should chime in here with a more authoritative opinion, but I believe it's a code violation to put a 30amp receptacle on a 20amp circuit just like it is to put a 20amp receptacle on a 30amp circuit.

If you used the single outlet configuration rather than the duplex 6-20 receptacles, that would be a visual cue that there's something a little different about the circuit as compared to the usual 120V branch circuit. And since the socket configuration of the 6 series receptacles won't mate with the blades of a 5 series plug, there's little danger of inadvertently plugging a 120V appliance into the 240V circuit.

[David Parker]

There is only a 100 amp service in a 20 slot box. Wellx2, Dryerx2, Stovex2, Clothes Washer, Bedroomx3, Outside Outlets, Kitchen/Bath, Fridge, Microwave/AC, Furnace, Living Room, Workshop, Workshop Lights, Air Compressor. 19 out of 20.

Hi Anthony,

I'm currently in the process of wiring up my small 12' by 15' basement shop. I'm using a sub panel because my 40 circuit main panel was full. I think of the sub panel as simply an extension of the main panel, giving me more slots to work with. I have a couple of questions / suggestions on your setup.

Your list above only gives 17 circuits. What am I missing? Is your panel approved to take half-height breakers? You need to read the sticker on the panel door to find out. My main panel specs allow slimline/half height breakers in only 10 of the 30 slots (giving me maximum of 40 circuits). My 20 slot sub panel is not listed to take any half height breakers. I would want to stay in code by following the panels' listed specs.

Based on your equipment leanings, if it was me, I'd want a minimum of the following circuits for my shop:
1) 240 volt 20 Amps for power tools - use L6-20R receptacle. I'd wire this with 10 AWG wire so you can easily upgrade to 30 amps if you need it in the future. Use a 20 Amp dual pole breaker with the L6-20R. Any other breaker is a code violation.
2) 120 volt 20 Amps dedicated to air compressor
3) 120 volt 20 Amps dedicated to dust collector
4) (Optional) 240 volt 20 Amps dedicated to future dust collector
5) 120 volt 20 Amps for power tools - I'd put at least one or two outlets from this circuit on each wall.

You already have circuits (2) and (5). You need to add another 120V 20 amp circuit and a 240V 20 amp circuit at this time. If you never plan to run your air compressor and dust collector at the same time, you could eliminate circuit (3) and just use the same circuit for your DC and air compressor. In this case, you could squeak by right now by moving your workshop lights onto a half height breaker, if that is an option allowed by your panel specs. This would give you 2 empty slots for your dual pole 20 amp breaker.

Have fun!
Dave

Edit: One other option I thought about. If your panel can take half height breakers, there is also the option of a Quad breaker (at least with Siemens panels). You could get one configured for one dual pole and two single poles or one configured for two dual pole circuits. These Quad breakers take up 2 slots in the panel.

[Travis Lavallee]

David,

Circuits 3 and 4 are essentially the same ones. All that needs to be done is to replace the receptacle and breaker on #3 to a 240V recep. and double pole 20A breaker.

[David Parker]

That's right. I guess I should have labeled it (3)(b) :).

[Anthony Whitesell]

Good catch Travis.

Taking it one step further, you could wire a 220V breaker in now with 12/3 cable to an double gang box with a 110V outlet and a 220V outlet in it. When the new DC arrives just unplug the old 110V DC and plug in the 220V DC.

[Anthony Whitesell]

The well pump, dryer, and stove each take 2 slots (220V appliances) and one for each of the three bedrooms (I think those are the 2 that missed the count).

#3 (120V DC) is on bedroom #3 (formerly an apartment in the basement created by the previous owner) circuit and is not combined with the workshop.

I have found that the basement lights in one half (laundry room side) of the basement are run from the living room circuit while the other half (workshop side) of the basement lights are on dedicated circuit that I installed. The workshop side half of the basement also has a single incandescent bulb fixture run from the master bedroom circuit (similar to the laundry/living room side). I'm thinking of moving the workshop side half of the lights to master bedroom circuit to "match". That would free up the other required slot to add a 220V outlet.

My door doesn't say if half height breakers are allowed. Even if they are, I'm still weary that the next buyer will balk at having 21 breakers in a 20 breaker box.

I see three items remaining to "complete" the shop; a SCMS, a jointer, and a larger DC. The SCMS is 110V. The jointer will probably be 220V but I can't run both the bandsaw and jointer at the same time (ie., only need one 220V circuit), and the larger DC would be 220V. I don't think the larger DC will be for a few years and maybe not even in this house, so I'll install the subpanel when I order the larger DC.