Good morning everyone. I have questions regarding running new wire for my table saw. I bought a Jet 3 horse cabinet saw, and I need to run wire from the panel to my attached garage. The saw gets delivered Monday, so I haven’t seen the cord for it. Tell me what I need. I was going to use a 30 amp breaker. Do I need 10-2 or 10-3? I’m assuming 10-2. I was also going to get the 3 prong twist lock receptacle and end for the plug. Any thoughts on this would be great.
Also, if I were to make an extension cord for it, would 15 feet be unreasonable? I would like to be able to move towards the garage door in the summer. Thanks for your help.
Replies
Doc, one question that needs to be answered is how many feet of wire from the panel to the outlet for the saw?
Will this be wired as 110 or 220?
You can use a 15' cord on the saw if it is large ennough wire. You will want to use heavy duty wire like SO cable. (the thick black rubber covered stuff).
Bill
I'm running mine off a 20A circuit with a 6R-20 receptacle that is fed by a sub-panel 20 ft away. The saw comes with a 14/3 cable so clearly it isn't pulling too many amps, I think 13-15 is the normal range for a 3HP motor, therefore 12 ga supply wire is adequate. Stepping up to 10ga and twist locks will run you another $50 in component cost for little, if any, difference in performance. Even though the circuit will require only red and black hots and a green ground, code will likely reqire that a neutral is present in the box as well even though it isn't hooked up to anything. Keep in mind that a circuit has to have compatible components. A 30A breaker requires 30A receptacles. You can use larger wire on longer runs The dealers usually have 30A circuits with twist locks since they want the ability to plug a 5HP 1 phase saw into the same outlet.
I mostly concur with what is said in .3, except that to say that 12ga. will suffice.
The required wire gauge (per the National Electric Code) is a function of 2 things.
One is how much current is being carried. #12 gauge is good up to 20 amps per conductor, over shorter distances. THe other factor is voltage drop, which is why I asked how far it was from the panel to where the saw was being used. There are tables which show distances vs voltage drop for a given wire and current. Keep in mind that you have to use the distance each way - i.e. if the outlet is 100' from the panel, there is a 200' run out and back. It's the 200' number that must be used in the voltage drop calculations. The farther you are from the panel, the greater the amount of voltage drop across the length of the wire and the less voltage that will be available to run your load. This is the principal reason that 220v is more efficient at running large tools than 110v. Since only half as much current is used at 220v, the line loss is half as much.
Bill
Thanks for all the replys. The saw doesn't get delivered until Monday morning, so I don't what the specifics will be in the manual. The run from the panel to the garage will be between 10 to 15 feet. I was just wondering about an extension cord because the garage is just a single stall and I was hoping to be able to move the saw and use it different places depending on what I'm currently creating. Also, wouldn't mind wheeling it outside the garage door when I'm cutting particle board or melamine. The people at ACME told me the saw would draw up to 18 amps, so I figured that a 30 amp breaker would be better to handle the draw on start up. Of course, there is a good chance I have no idea what I'm talking about. Thanks again. I'll probably write more when the saw arrives on Monday, but I welcome any more thoughts between now and then.
When I got my saw, I considered replacing the "too short" 14 ga cord with a longer 12 ga cord for flexibility. It comes without a plug. This turned out to be more complicated than I thought since the cable runs through several grommets in the cabinet. I decided instead to have additional 20A boxes put in the garage since it was likely I'd have more 220 machines down the road anyway. FWIW, the additional cost of wiring 20A receptacles with 10 gauge wire is trivial (2-3 cents a foot per cable), and will save money if in the future they need to be rewired for 30A use. I used 12 ga simply because I had spools of it already and the run from the sub-box was fairly short.
As for an extension cord, I can say that you might want to physically look at the plugs first. 10 gauge rubber cord is pretty thick and might not fit into the standard inexpensive yellow plugs found at the big boxes for about $4 a pop.
I looked at all the tools I expected to buy and decided that I could standardize on 220V 20A receptacles. The exception will be a 180A mig welder which will need its own 30A circuit.
Here is a copy of the manual if you just can't wait. ;-)
http://www.wmhtoolgroup.com/JETGeneral/Manuals/Woodworking/Manuals/JTAS10XL.pdf
I'll also be curious to hear your comments about moving it around. Its quite a load on the mobile cart, and futzing with the DC hose has limited my saws mobility to side to side movements of 3 ft or less.
Doc,
Gettin excited yet? It's gettin close....I was kinda scared to turn it on..asked the electrician to turn it on for the first time.
Jet Boy is correct...moving these puppies around a lot just does not happen. I have a very small space too and most of the movement is to accomodate cutting stock eg. full sheets or side panel of a large cabinet....fairly limited movement, a few feet.
Also, like everything else in a small shop, the TS is integrated into it's environment. In addition to the dust collection (shop vac), I built a shelf around a lolly column next to the TS to hold the blades, wrenches, some measuring tools, etc. it is very handy. Lastly, I built a drop down outfeed table, a few months ago, which has just been fantastic....but also has added a bit of weight to the monster.
My experience has been that a cabinet saw changes everything. I needed time to rethink the who, what and where...more jigs, addons, nature of projects changed...with the new quality, power and capability...your going to have a ton of fun...
>Even though the circuit will require only red and black hots and a green ground, code will likely reqire that a neutral is present in the box as well even though it isn't hooked up to anything.<
Is this true? I am redirecting a 240volt / 30 amp circuit that was once used for a heavy window aircondition unit and was wired with 10/2 - just a red, black and ground wire in the box. The circuit fed only one outlet (the window unit) and was left unused when the house was changed to central heat and air. Do I have to rewire with 3 wire to have neutral present in the two outlets I plan to have in my basement shop or just redirect the circuit down there with 2 wire as is?
Another question, just out of curiosity , for those electrical code gurus - When they put the CH/A in this house and left this circuit unused, they simply cut the wire at the box for the window unit and covered it with a blank plate, leaving 240 volts present in the box. They didn't even identify that both leads were hot with red tape. That seems like pretty shoddy work to me. Am I correct?
Here's another one - when I first tested the circuit with a multimeter, I was reading something like 250-255 volts. After cycling the breaker at the subpanel (maybe the first time it had been cycled in years) I read a nice clean 240 volts.
Thanks for help. Ed
I guess I should have said "may require" a neutral. Depends mostly on what the local jurisdiction requires. Lots of 220 appliances now have electronics that need 120, so you need a neutral for return, hence new stuff tends to get put in with 4 wires being pulled. Doesn't make sense for 220 tools, but I don't make the rules. On the other hand, if 4 wires are pulled at the get go, that single 220 receptacle can become a pair of 120's down the road.
As for your box, there is code and there is shoddy workmanship. At a bare minimum, the cables should have been properly terminated with wire nuts in the box. Was the breaker on when you started? How old is the breaker and wire, and in what condition? Might be wise to start with all new components.
Yep the breaker was on and the wire looked liked it had been cut with a big pair of pruning shears. I was surprised when I first removed the blank plastic plate at the outlet, applied my multimeter leads to the two copper wire ends and read 240 volts. I never would have thought they would leave an unused circuit live like that. Then I traced the wiring back to the subpanel and was happy to see that it ran right through my basement shop and to a thirty amp breaker at the subpanel. I'd estimate the wire and circuit breaker is about twenty years old - good condition 10/2.
1. No code requirement to use a neutral if there is no neutral load. Common sense would dictate 250V, 2P, 3W plugs wouldn't be available if they didn't meet code. The starter on the Jet works on line volatge therefore no neutral is required.
2. Actually the ampacity of 75*C cu. conductors for #14 is 20A, #12 is 25A and #10 is 35A. Code limits the breaker sizes to 15A, 20A, & 30A respectively. I have no idea why.
3. Voltage drop is calculated all the way back to the transformer. Normal practice is to allow 2% in the feeder to the panel and 3% in the branch circuit. The max. 1 way distances for a 3hp, 240V motor circuit are 112' for #14, 178' for #12 and 284' for #10.
4. Efficiency has nothing to do with voltage drop. Eff = Output Watts / Input Watts. An induction motor will try to achieve it's rated output. Ignoring power factor to keep it simple, wattage = volts x amps so as the voltage drops the current increases.
5. I have (3) 240V receptacles in my shop using #10 wire, 30A breakers and NEMA type L6-30 twist lock receptacles. I do move my Jet cabinet saw around (Vega Machine Mover) a lot so I made a 10-3 SO extension cord 12' long. No worries even with the 5HP planer/moulder.
6. The 5' #14 cord on the saw is negligable because it's so short.
John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
Thanks John,
What is a good book to have on your shelf that summarizes code? I think you mentioned Ugly's in another post - is that the one? Looking for one step beyond the basic Black and Decker Home Wiring books but one step short of being a licensed electrician.
Looking to be the kind of guy that draws a wiring diagram, gets a permit, does the wiring, then pays a licensed guy/ city/county inspector to check the work. Thanks Ed
Ugly's will give you everything you need to figure loads, and size wires, breakers and conduits appropriately. Beyond that there's an anotated vesion of the NEC that explains the code sections and provides examples. It's probably around $100 though! There's probably something in between if you check with a techinical book store they may be able to help. You're probably not going to find anything on workmanship outside of text books for electricians. My employer furnishes the NEC, but I bought myself an ElectriCalc Pro from Canculated Industries for around $100. These are the same folks that make the Construction Master calculators. It handles all the basic calculations and sizing per code and has a replaceable plug in module for when the code is revised.John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
I would only add that the percent voltage drop limitations are Fine Print Notes (fpn) in the Code, and therefore not enforceable. But it is good practice to follow them, especially with motor loads. And the max distance out for 120V is one half that for 240V, at the same percent voltage drop (same current but half the initial voltage, so you need half the impedance).Be seeing you...
"I would only add that the percent voltage drop limitations are Fine Print Notes (fpn) in the Code, and therefore not enforceable."
In theory maybe, but in reality anything in the code can be and is enforced. Inspector's follow the "Golden Rule" - He who has the gold (final permit sign-off and meter release) makes the rules. John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
Doc,
Just a couple of points. My Grizzly said to provide for 20 amp pull..so I set it up for those numbers buying everything compatible. I also gave myself an extra 10" of wire ...and avoided the extension cord. Lastly, I had an electrician come in for 20 minutes and do the final hook up...check everything...cost me $60 bucks for his time.
Just to add to the confusion (and maybe someone out there can clarify), the code requires a dedicated 30 amp circuit for a three HP motor, yet my Delta 3HP planer came with a 20 amp plug.
I believe that you have the option of sizing the circuit according to the manufacturer's direction.
I believe that you are also allowed to size the circuit according to the face plate aperage.
A dedicated, continuous duty, 3 hp, 230V motor circuit, whether cord and plug connected or hardwired would require #12 conductor based on 125% of the full load current of 17A. The breaker could be on an Inverse Time breaker up to 45A (250% FLC rounded up to next size). If you used an trip instantaneous trip breaker it could be 800A and wire would still be #12. This provides short circuit and ground fault protection while eliminating nuisance tripping on inrush. By the way induction motors over 1 hp require overloads which is why they come with starters instead of switches.
Now enter the receptacle. If it is dedicated to a motor then the foregoing motor circuit criteria apply. If it's bolted down it's considered stationary and the circuit is dedicated. If you can plug something else into it than you size it according to the criteria for plugs and cords. Starting with the load 12A is the max on a 15A plug with a 15 or 20 A breaker, 16A is the max on a 20A plug with a 20A bkr and 24A is the max on a 30A plug with a 30A bkr. Still with me? Now for the cord. Assuming Type SO cord, the max loads are 18, 25, & 30A for #14, 12 & 10 respectively.
So a nominal 3hp, 230V motor drawing 17A on a non-dedicated, plug and cord connection at minimum would have a 20A bkr, #12 wire to a 30A plug and #14 SO cord. Since you need a 30 amp plug anyway then you'd want to use #10 wire and a 30A breaker to take full advantage of the allowable 24A.
But your planer came with a 20A plug, so what gives? If you check the nameplate you'll probably find the FLC is less than 17A so a 20A plug is legal. You may even find the supplied cord is #16 which depending on the type could be good for as much as 15A.
Hope this helps.John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
Okay, you know the part where you said "Are you still with me?" I have to be honest, I was lost long before you said that. I'll tell you what I want, and maybe we can go from there. I've done quite a bit of "at home" wiring of just household outlets and lights, but the technical lingo sinks me. Which of course leads me to believe that I shouldn't be wiring this. But, if I'm told exactly what I need, I'm fully capable of doing the actual wiring, which is why I always get the exact details of what I need from a good source before I do the work.
Okay, with that said, here we go. I bought a Jet cabinet saw with a 3hp motor. It will be in my one stall attached garage. The electrical panel in the basement is on the wall below that is the shared garage wall. In other words, I don't have very far to go with the wire from the panel to the garage......just a few feet. I would like to put in an outlet and breaker that is designated for just the saw, with the ability to plug in a planer or welder perhaps in the future into that same receptacle, but not necessary. And of course I would only ever be using one piece of equipment at a time. I do not plan on putting any other lines onto that breaker. I would also like to make an extension cord so that I can wheel the table saw out the garage door in the summer time and keep some of the dust outside. The extension cord would only have to be about 20 feet long at the most.
I've purchased (still in the bag) a box of 10-2 wire, a 30amp receptacle, a 30amp plug, and a 30 amp breaker. None of this is for the extension cord. The receptacle and plug are the twist-lock type. First let me know if this will be okay for its intended use, and then let me know what I should do for constructing an extension cord. I assume it would be the same type of male/female plugs, with a 10-2 wire constructed for use as a cord.
Or maybe I'm wrong, and I should have 10-3. I haven't taken the saw out of the box yet as I would like to get the garage ready before I put it together. Again, any assistance would be great. Thanks.
The plug and receptacle should be NEMA Type L6-30R. Your 10-2 Romex should have a ground wire besides the 2 #10's. Tape the last 6" of the white wire with black tape at both ends. White is reserved for neutrals, which you don't have or need. The 30A, 2 Pole breaker is fine, but if you're going to push the saw outside, a ground fault breaker would be ideal.
For the cord you'll want 10/3 Type SO or similar. Romex and cord are designated differently hence the different designations. They probably do that just to screw with non-sparkies :).John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
Okay, I'm back from snowblowing the entire neighborhood. Getting lots of snow. My plug and receptacle are both Pass&Seymour. The plug is a Turnlock L630-P and the receptacle is a Turnlock L630-R. So, I'm guessing that I got both of these right. Can you get a ground fault receptacle of this type, or do I get a ground fault breaker instead. I see you recommended a ground fault breaker, but wasn't sure if the receptacle itself was available in ground fault. Thanks again for all your help.
I've never seen a GFI like that and if they do exist they'd be spendy. The breaker would be cheaper. I only mentioned the GFI out of conscience. I don't have GFI on my outlets and sometimes roll a machine out into the driveway when working with real long stock. John O'Connell - JKO Handcrafted Woodworking
Life is tough. It's tougher if you're stupid - John Wayne
You wrote"
"But, if I'm told exactly what I need, I'm fully capable of doing the actual wiring, which is why I always get the exact details of what I need from a good source before I do the work."
If you don't know what you are doing, hire the work done. Noone here can either tell you exactly what you need to do or watch you well enough to ensure you don't make mistakes.
My question was not in regards to "how" to wire it, but what exactly I "needed" to wire it. Having never owned a cabinet saw, I wasn't sure what was needed to get it wired correctly. As far as running wire, wiring it in the panel, and installing a plug or receptacle, I believe I'm fully capable. I'm sure that most of the information I needed could be gotten from the Jet manual, but the saw is unpacked and being stored until I can get heat in my garage. That's why I asked for a little guidance from anyone out there who has already been through this.
I'm sure if I give advice to someone on how to cut tenons on the table saw, there is a chance they could cut there fingers off. Granted I'm not there to look over their shoulder, but it seems to me that this forum was designed to give people advice, assistance, and guidance as they learn or attempt new things.
When it comes down to it, you are right. I likely shouldn't be wiring this myself. And I'm sure that people like me irritate all of the electricians out there by attempting it myself. But thank you to all of you that have given me advice in lieu of my reckless endeavor.
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