220v Extension Cord for New G1023SL

[Hank Keller]

I'm taking delivery of my new grizzly this wednesday and in preparation have purchased 22 feet of 4 wire 10 gage water resistant wire along with a plug and socket. Will the 10 gage wire be okay?

Next thing to get is the mobile stand at the woodcraft store during my trip up to detroit this weekend.

Thanks.

[Hoa Dinh]

First off, I'd just skip the extension cord. I'd rather replace the supplied cord with a longer one. It is cleaner, safer, and probably cheaper (1 long cord + a plug vs a short cord + a plug + a socket).

You don't need 4-wire cord because there is no neutral. There are only 3: hot, hot, and ground. For 3 HP motor, 10-gauge is more than sufficient.

IIRC, the plug in the photo is for 120V, 20A plug. I think 240V, 20A plugs have two horizontal bars, not one horizontal and one vertical (I'm writing this totally based on memory. There is a good chance that I'm wrong here).

Edited to add: I was wrong about the plug :o (I warned you, right?). The plug and socket in question are 250V, 20A. The plug with two horizontal bars is 250V, 15A. Mike Cutler has the correct answer.

[Joe Mioux]

Do you really need a 20 foot 220v extension cord? And I would think that 4 wire is unnecessary.

Someone, here, will give you the proper answer, but I would think that you might be better off with half that length for your saw.

Just my uneducated .01:)

Joe

[Rick Christopherson]

All of the above comments are correct, including the comment on the plugs you bought. It is OK to use the 4-wire cord, but you just won't use one of the conductors.

Unless you have a specific reason for wanting an extension cord (like for swapping with other tools) I would replace the factory cord with the new cord you bought. In any event, I would not use the 120 volt cord caps, otherwise you could accidently plug the saw into a 120 volt outlet.

New Edit: My mistake. I don't use this forum enough to realize the pictures are just thumbnails that can be enlarged. As soon as I clicked on it, I realized the two cord caps are the correct NEMA 6-20's.

[Mike Cutler]

Hank. That length of cable will do very nicely. Use it as an extension cord, or lug it and replace the cord that came on the saw. Don't worry about the extra conductor. It's not hurting anything, it's just there
Make sure you get the right the plugs and sockets. I'd recomend twist lock plugs. a little more positive engagement.

[CPeter James]

I use L-6 20 twist lock plugs and type "J" cordage. As others said, the extra wire is ok but the wrong plugs a a no, no. I burned up a Milwaukee 1/2" corded drill many years ago while installing some equipment in a new restaurant. I plugged it into a "normal' wall outlet that some numb electrician had wired for 240V and since he did not have the correct plug, just used what he could find. That drill cost $130, 30 years ago and I was P....d! I have standardized on the L-6 20 for all of my 240V stuff and use 20amp breakers with no problem. I have a PM66 3 hp, a Jet 15" planner with a 3 hp motor, and several other things that have smaller motors, 2 or 1 1/2 hp.

CPeter

[Casey Hand]

3 hp motor should be around 15 amps; at ~20 ft 14 gauge is actually heavy enough. 12 is good for 20 amps up to 50 ft and would be what I'd recommend (I run a 3 hp Unisaw and shaper off of 50ft with no noticable difference than if it's plugged right in). 3 conductor is all you need, hots are interchangable. 10-4 will of certainly be fine, provided the plugs are meant to take that large of an OD jacket, could be a real snug fit. Those are the appropriate plugs, have fun getting it in 'em :)

[Gary Curtis]

I just got a General TS with a 5hp motor. I asked my building contractor to wire my shop for big stuff. Plug access was a problem, and I had on hand a 3 wire "borg" 220 extension cord. It is 12 feet long, with molded male/female 20-amp (rating) plugs. But it is only 12-gauge wire.

I turns out I didn't need it. But 20 amps is certainly big enough hardware for a 3 hp motor. And I agree with the fellow who said "Replace your cord with a longer one, rather than an extension cord". I wouldn't feel comfortable with an extension cord less than 10-gauge, especially if you wanted a 20-foot run.

Gary Curtis

[Mike Cutler]

Are we saying that the plug and receptacle in Hank's picture is incorrect for this application.?

That plug and receptacle in Hank's picture are a 250/20amp plug and receptacle, if I'm not mistaken.

A 120/20amp gives you the horizontal/vertical to the left of a vertical with the ground pin at the bottom. The 220/20amp gives you a horizontal/vertical to the left of a horizontal, with ground at the bottom. They look like the correct plug, and receptacle for the rated application. I would still use twist locks though.

I hope I'm not wrong here, because I have those same plugs and receptacles connected to 5 machines.

Hoa. I believe that two horizontal bars is a 250/15 amp plug/receptacle.

[Rob Russell]

The plug and connector body that Hank has are a mating 6-20P and 6-20C. Those are rated for 20A @ 250V. I can clearly read the lettering on the plug, at least on my computer and that's without going to a NEMA configuration chart. According to what I could find for specs on 10/4 SJOOW, that's about the largest diameter you can fit into the Cooper plugs/connectors.

There is one other option you have for wiring your saw. Use all 4 conductors and put a 3-pole/4-wire grounding plug on your extension cord (2 hots, "neutral" and grounding). Wire in a 3-pole/4-wire grounding receptacle on your wall to plug this into. The plug/receptacles would be 14-20R/P for straight-bladed or L14-20R/P for twist-locks.

Mount a 4 11/16" x 4 11/16" x 2 1/8" deep box on your saw. Buy the cover to mount 2 devices. Install (1) receptacle to match whatever plug is on your G1023SL and (1) 20A/125V duplex receptacle. Use the 2 hots and grounding conductor to feed the 240v receptacle for the saw. Use all 4 conductors and split-wire the 120v receptacle. This would give you a convenient receptacle on your saw to plug in things like a router if you build in a router table to the saw's extension table. Just a thought. If any of the above doesn't make sense - holler.

Rob

[tod evans]

rob, did i read this correctly? are you suggesting pulling a 120v line from one leg of a 220v feed?

[Michael Adelong]

I actually got lucky when changing the 240v outlet in my basement from a range plug to a 220v 15A circuit.

I looked at the BORG for about 2 weeks. They all sell the 240v 15A plug (ground +2 horizontal blades), but they never seem to have the 220/15a outlets. After about 3 weeks of looking, I found 2 of these combination outlets (http://www.levitonproducts.com/catalog/model_5031-I.htm?sid=761736D12D73E143B99824C02863EE1E&pid=1208) on the bargain table at the BORG close to my office. Looks like I got a great deal, too. Only paid $2 each. I installed 2 of them in one double gang box. Now I have 2 115v and 2 220v 15A circuits in the same box. I highly recommend them for the convenience of running only 1 conduit, and 1 set of boxes around the shop. I didn't look to see if there is a 20A or 30A version of them.

Internally, those outlets are wired exactly as Rob described. The neutral and one of the hots go to the 115v outlet, and the other hot only goes to the 220v outlet. I wish they had 10 of these on that bargain table. I'd love to have 220 and 110 in every outlet in my shop.

For my tools, I have been doing is buying the yellow heavy duty extension cords (12 gauge) from the BORG and cutting the ends off. I then hard wire one end to the tool, and put a plug on the other. Fast and easy. When I priced it out, buying the extension cord & plug was cheaper than the piece parts to build what Hank is building now. I also like the bright yellow color and the fact that the extension cords flex much better than the black rubber coated wire.

Michael

[Mike Cutler]

rob, did i read this correctly? are you suggesting pulling a 120v line from one leg of a 220v feed?

Tod. That was one of the suggestions that I was going to make. It's actually done quite alot. There is even a special receptacle to accomplish this. all of the splitting is done inside.
There are many houses in New England where 220 was pulled up into the attic,or top floor, and split in half to provide 115 throughout the top floor. You do have to be careful about balancing out the loads, and not challenging the ampacity of the neutral return.

Additionally there is a breaker available, I know it as an "laundry breaker". It is 3 mini breakers that occupy the space of a single 220 breaker. It has a 220 breaker, and two 115 breakers seperated out in the molded case. It is used for laundry room applications. 220 for the dryer, 115 for the washer, and 115 for the dedicated convenience receptacle.

[tod evans]

not being an `lectrition i`ve always been told not to pull 110 off of a 220 line? so i just don`t do it unless it`s a jobsite temporary deal. i just wondered if doing this was within code? tod

[Mike Cutler]

Tod. I'm not a liscensed electrician either. I just make the power.
I can't speak to the code, we do have some liscenses here on the board though, but electrically speaking 115 is being pulled off a 220 feed in the breaker panel. All of your 115 breakers are split off of one leg of the 220 with a common neutral return, so to speak. You do have to be careful about the neutral return. It has to be sized large enough to handle the currents.
Code wise though, we'll have to let the experts chime in.

[Rob Russell]

Tod,

Yes, I'm suggesting pulling a 120v circuit from the 240v circuit. It's fine if done properly.

When wired as a branch circuit where you have 2 hot legs (with 240v between the hot legs) and a common neutral, that's called a multi-wire circuit. IMO, the NEC is actually a bit lax on this type of circuit. All it requires is a common disconnect if both hot legs are used on a single device, i.e. if you "split-wired" a receptacle so the top outlet is leg A and the bottom outlet is leg B. It would be NEC-compliant to actually have a pair of single pole breakers to feed the 2 hot legs as long as you didn't use both legs on the same device, for example if you alternated receptacles - duplex receptacle #1 on leg A, then duplex receptacle#2 on leg B,duplex receptacle #3 back on leg A, etc. Personally - I wouldn't do it that way. All the multiwire circuits I've run in our house used a 2-pole common trip breaker. If 1/2 of the circuit causes a trip - both halves are going down.

I'm guessing that there has always been a bugaboo about pulling a 120v circuit from a 240v circuit because of 2 things - lack of a 2-pole common trip breaker and lack of a proper neutral. It would be flat wrong and dangerous to create a 120v circuit from a 240v circuit by using the equipment grounding conductor as the neutral. It would likely work, which is why people did it, but it effectively makes the equipment grounding conductor a live current-carrying conductor and that's a potentially deadly situation.

Rob

[Frank Chaffee]

Hank,
If I may ask of the knowledgeable responders to your original question,
For the purpose of understanding circuitry of duo voltage runs,
I can see how two 120V hot legs 180° out of phase can share a neutral wire in a 240V circuit, but I do not understand how that same neutral wire can also serve a separate 120V circuit that could be used simultaneously.
HELP!
Rob, you may have already explained the situation I am confused about, but, and I apologize, I still don’t understand.
Frank

[Rob Russell]

Frank,

A 240v single-phase circuit doesn't use a neutral. The circuit actually only needs the 2 hot legs to run, although any 240v circuit will include an equipment grounding conductor as a "safety ground".

Here's an example of a 20 amp, 240v circuit, with neutral to provide for 120v loads.
- assume that you've put in 120v outlets for both hot legs.
- assume a 10 amp, 240v motor load
- assume a 5 amp, 120v load running on leg A (let's say running a small power feeder)
- assume a 3 amp, 120v load running on leg B (I'm stretching here - maybe a mini-vacuum pump to run a vacuum hold-down).

The net current returning on the neutral would be 2 amps. The calculation would be (0 amps from the 240v motor + 5 amps from leg A - 3 amps from leg B), giving 2 amps.

The reason for this is what you've already pointed out - that the 2 hot legs are exactly 180 degrees out of phase. On a 240v motor, the amount of amperage drawn through each leg is equal, so the 2 legs cancel each other out. On the 120v legs, you need a neutral for the current to return.

If you had 2 equal, 120v loads running on opposite legs, the currents running through the neutral would be just like a 240v motor - they would cancel each other out. Normally on a multiwire circuit, the amount of current that will flow back through the neutral will be the unbalanced load between the 2 hot legs.

It's important to note that on a "normal" 120v circuit (i.e. not 1/2 of a "multi-wire circuit" with a shared neutral between 2 hot legs), the neutral carries the same amount of current as the hot leg. If you put an ammeter on the neutral when you were running a router that's drawing 12 amps, you'd see 12 amps flowing back through the neutral to your electrical panel.

Rob
Addy protocol: not a licensed electrician

[J. Greg Jones]

This thread has been very interesting and has given me some ideas for getting 240v into my garage. One thought that I have is that my laundry room with 240v for the dryer is on the interior/garage wall, just where I would like a 240v outlet to be in the garage. The dryer is fed with a 30 amp, 240v circuit. Would it be possible, safe, and within code, to junction off the existing 30 amp, 240v circuit and put in a 240v receptacle and (1) split-wired 20A/125V duplex receptacle like what Rob describes above?

[Mike Cutler]

This thread has been very interesting and has given me some ideas for getting 240v into my garage. One thought that I have is that my laundry room with 240v for the dryer is on the interior/garage wall, just where I would like a 240v outlet to be in the garage. The dryer is fed with a 30 amp, 240v circuit. Would it be possible, safe, and within code, to junction off the existing 30 amp, 240v circuit and put in a 240v receptacle and (1) split-wired 20A/125V duplex receptacle like what Rob describes above?

Greg.

It is always possible to do this. It can be safe also, assuming that the dryer would not be in use. I don't believe that it is allowed per code though.
When we put in our laundry room. The 220 for the dryer, the 115 for the washer, and the 115 for the convenience recpeptacle all(each) had to have their own dedicated breaker. This was in Connecticut in 1993. It may be different now, but I don't think so.

[Mike Evertsen]

are you sure you got the right plug because both of my grizzly machines my grizzly DC and my unisaw have plugs like this one

http://www.elect-spec.com/ustrp_811ewcordx1ab.gif

[Rob Russell]

Greg,

The answer to your question is maybe. Is your dryer fed by a 3-wire or 4-wire circuit? If the answer is 3, then you need to rewire the circuit because it's an older circuit and doesn't have an equipment grounding conductor. I'm saying 4-wire vs. 4-prong plug on your dryer because a creative electrician (read unknowing homeowner) could have put a 4-prong receptacle in and incorrectly used a 3-wire circuit to feed it. If your dryer plug is only 3-prong, it's almost a certainty that you have to rewire the circuit. If it's got a 4-prong plug, I'd kill power to the circuit and check either the receptacle or the breaker panel to ensure that it really is a 4-wire circuit.

The code used to allow new 3-wire circuits for 240v ranges and dryers. The neutral was needed because of the 120v loads like lights or clocks. The frame of the dryer/range was also bonded with the neutral, so the neutral served as the equipment grounding conductor, which isn't right. The code currently requires 4-wire circuits for dryers/ranges, but existing circuits are grand-fathered in as an exception. The NEC article on this, if you care to read it, is 250.140.

So - if you have a 4-wire circuit, you can do what you want to do.

Mike,

The code would currently require at least 2 and possibly 3 circuits to have a 240v dryer and (2) 120v circuits in a laundry. I'm not aware of any prohibition in the NEC that says you can't run a 240v circuit for the dryer and pull a 120v circuit off of that. What the code does require is a dedicated 20 amp, 120v "laundry circuit" for the washing machine. Since most electricians are not going to pull a 120v circuit off of the dryer circuit, they'll install (1) 240v circuit for the dryer, (1) 20A/120v laundry circuit and optionally (1) 15A or 20A, 120v convenience circuit in the laundry room. The latter is what I did when I wired the laundry room in our addition. Note that, if you have a sink in the laundry room, any convenience receptacle within 6 feet of the sink must be GFI-protected. There's talk about the laundry circuit needing GFI protoection too, but that would be a change in the 2008 code if it's accepted.

Rob

[Rob Russell]

Mike Evertsen,

That plug looks like a 250v/15A plug to me. We're talking about dryer plugs which are a whole lot bigger and have a whole lot different configuration.

This link shows the plug configurations - http://www.leviton.com/sections/techsupp/nema.htm.

Rob

[Mike Cutler]

Rob.

When we put in our laundry room, it kinda threw everyone for a loop.
Our washer and dryer are Asko's from Sweden. The Washer runs off of 115 and 220, it has an on demand hot water heater built into it. It also plugged into the back of the dryer, which is plugged into the 240.

I remember asking why I had to put in two dedicated 115's when the washer plugged into the dryer, and I would never need the third, and have never used the other 115 receptacle.
Bottom line, that was what had to be there. No use fightin' city hall eh..

This is also why I know about the "laundry breaker". The 115 is paralleled off of the 220, it's just done at the breaker is all. A single 220 space, supplies 1-220 breaker, and 2 115's. Pretty slick.

Moral to this story. Don't be the first person on the block to have some new fangled swedish washer/dryer in 1993. :eek: ;).

I always advise to bring in a local liscense. They know what the building inspector wants to see, and they do it for a living, everyday.

PS. I argued a liitle more about running Hot and Cold water to a washer that didn't use hot water. I lost that battle too. :rolleyes:

[Rob Russell]

... I remember asking why I had to put in two dedicated 115's when the washer plugged into the dryer, and I would never need the third, and have never used the other 115 receptacle.
Bottom line, that was what had to be there. No use fightin' city hall eh..


You might not have needed the circuits, but the next homeowner could have because they didn't have a fancy-pants Swedish washer/dryer. The town was just making sure that the laundry was installed to meet the then current, local, adoption of the NEC.