Concerns about electrical – 1st big power tool
Hi folks, After years of beg/borrow/steal/mooching off of generous friends’ power tools, I’ve worked up the guts to start making my own investments. I am considering serious machines ($700-2k). Leaving aside the question of WHICH tool to buy first… I ran into a big wall of my own ignorance when I realized that most serious power tools for home shops run off 220V. My question is: how big a deal is it to set up a 220V circuit? I do have several open slots on my breaker panel… What wallet-damage could I expect from hiring an electrician to set me up with 220V? On the other hand, if I go with 110V, I’m concerned about the current load. All my existing breakers are 15A and 20A rated, which I assume means the wiring in the walls is no better than 14- and 12-gauge. I figure 1.75hp is safe if I devote a circuit to it. But, eg the 2hp WoodTek hybrid saw motor is rated for 20A… can I run that on a 20A breaker or do I need to upgrade? Is there a rule of thumb for sizing a circuit (breaker/wiring/receptacle) somewhat larger than the device you plan to run? Or can I just say “20amps, ok, my breaker is 20amps, check” ? Also, is there any reason I would want to choose 220V over 110V? Thanks so much for any advice you can give. Sincerely, Melissa
Replies
The reason for choosing 220 is that you can use higher power. If you choose equipment that will run on either 120 or 240 volts, there is no difference as long as you are on a dedicated circuit with a moderate length run to the box.
As far as hiring an electrician, that cost will vary quite a bit regionally. But you would save a lot of money if you did the grunt work--installing the box and running the wire, leaving the electrician to only make the hook up. You have to gauge for your self how comfortable you are doing the work.
If the wiring goes to the sub-panel, then you can work with power off when you make the connections of the wiring to the breakers. If you would be adding the new circuit to your main breaker box, then power could still be live and working in the box requires more care.
If you should run a new circuit anyway, then you might as well make it 220--it's almost the same deal--the receptacle is different, and the breaker takes two adjacent slots not just one. Up to 3 hp. you can use the same wire--12 gauge, though if it's not a complicated installation you might as well use 10 gauge, for more money, but the ability to upgrade down the road.
I ran my own 220v line from an unused drier line. Cost was some 12 gauge wire, an outlet, and a plug (~ 35). It was a simple 2 hr job.
Thanks for the advice, everyone. I guess I don't have a sub-panel-- the service wire comes off the street right into the only breaker panel in the house. I've run romex before but I'm not confident going into the panel.
So, I am going to have an electrician come out and give me two shiny-new 240V circuits: one for a big machine, one for a dust collector :-)
thanks again,
Melissa
FWIW, Melissa, I think the first decision is whether the nature of the work you'll be doing actually requires the HP that puts you in the 220v category. If you're working mostly with 4/4 stock, for example, you may not need monster machines. Why pay to crank up a 3-5HP motor every time if 1-1.5HP is all you need?
Even with 110v machines, it's handy to have a good number of outlets around the shop running off several 20A circuits. Check your breaker box to see how many blanks you have, and then decide whether it might make sense to have the electrician install a sub-panel for additional breakers.
definitely better to oversize the current load to be safe -
SA
Going to 220 V will not give you more power. P=V*I*pf. When the volts go up, the amps go down. Look at the nameplate on a dual voltage motor and you will see this illustrated. The advantage of 220 V circuits is smaller wire size, controllers, breakers, conduits, etc.
The answer to your capacity question is found in Article 430 of the National Electrical Code, Table 430.248. you cannot use the motor nameplate full load current to size the conductors. Also the conductors must be rated at 125% of the value in Table 430.248.
For example, a 1-1/2 HP motor has a Full Load Amperage, (FLA) of 20 A at 115 V and 10 A at 230 V, from the Table. So the wire/breaker must be sized for 25 A @ 115V or 12.5 A @ 230 V. For 115 V that would mean a 30 A Breaker and a # 10 wire. For 230 V, 20 A Breaker and # 12 wire.
You might want to consult a qualified electrician to save yourself some money/heartache.
Best regards,
Fred
Hello Melissa,
Welcome to Knots, and I guess your fist post makes you an official Knot head.
I see in your picture that there is some kind of strip rowing shell or kayak. Is this the type of work you will most likely do?
I agree with others here, if you are not comfortable working with electricity you should hire an electrician. I have only one 220V circuit in my shop and it has never been a problem for me to unplug one machine and plug in the next. I work alone and never use more than one machine at a time. I do have space in my sub panel for a couple more 220V circuits should the need arise, a larger dust collector for example, but for now the one circuit works out fine.
What types of power tools are you considering? Perhaps a better description of your intended work will help us Knot heads give better advice.
Hi Bob,
Yup, that is my kayak (such as it is so far). I used that pic because it encompasses my 2 fav hobbies (3 guesses!). That project kind of goes on and on in the background; someday I will finish it (really!). Tell you what though-- the guy whose table saw I mooched to rip all those strips, I had to buy him a new blade and a case of beer!!
In general I seem to be really interested in curves (steam bending, laminating, and incorporating curves into designs). My first furniture pieces were 2 coffee tables with bent legs and a rocking chair for my Mom.
My next big project will be a crib for my best friends who are expecting (!).
Anyway, I've more or less decided my first purchase will be a table saw. (Well, I guess the FIRST purchase was a router.) Was kicking around the idea of getting a bandsaw first, so I could resaw thick stock into thin pieces for laminating, and cut round table tops and stuff. But I can do the latter by hand, and the former (1) scares me more than a little and (2) I don't know if I'm good enough with my hand planes to smooth the resulting pieces... and don't have a jointer.
Re: the two 220V circuits: large dust collector + 1 big machine at a time is exactly what I was thinking.
Thanks for the welcome!
Melissa
"Yup, that is my kayak (such as it is so far). I used that pic because it encompasses my 2 fav hobbies (3 guesses!). That project kind of goes on and on in the background; someday I will finish it (really!)."
Do you work for NCIS? (If you don't watch the TV program, you probably won't get the joke.)
Once you purchase a good bandsaw, I suspect you'll find it indispensible. I do, as do many others here, I think. Once the bandsaw is tuned properly, resawing is much easier than I had thought. Plus, the bandsaw is one of the safest machines in the shop (as long as one remembers they are also used for cutting meat).
Definitely get 220- opnes up so many more options for equipment.
When we moved to current house, the workshop nee basement had a few outlet/light circuits, and a circuit to washer/dryer. Fortunate to have 200 a service into house. I was chicken to go into primary panel, so I hired an electrician to put in a 100a breaker in that panel, and run wire to a new panel in the basement. Then I was good to go -I could turn off the breaker on the main panel and go to town.
BTW - I have one primary 220v circuit going to DC, TS, jointer, planer. Only 2 things can run at a time (DC +1) so I've never blown the circuit.
If you've never done this
If you've never done this work before always go to an electrician. Also, I would suggest that if you need 2 outlets, have 3 installed. You pay for their time and the cost per outlet is lower...
I'm fascinated by this. With
I'm fascinated by this. With the systems I am familiar with (Malta and some European ones) we have 220V single phase (1 live, 1 neutral and earth (ground)) or 3 "hot" wires, neutral and ground for 415 volts. 3-phase supplies must be specially installed by the Power company and have a separate meter. You can then get 220V by connecting 1 phase and neutral.
With the American system is it a case of 2 phases to give you 220V, ie both wires to an unearthed device are live?
US 220 V systems are single phase. A neutral wire is derived by grounding, (earthing if you are from the EU), the transformer winding center tap. That configuration gives you 110 V between each leg and the neutral or 220 V across the full winding.
I don't think US Utilities will provide a three phase service to a residence. They will, under the right circumstances, serve a non-commercial shop, though.
Thanks northouguy/
Good point - also - all of my 220v outlets are the 110v/220v duplex stype. Each box has a 220v and a 110v, which has worked out very well for me - my 220 gear dont' move, but you never know when you will have a 110 item roaming around looking for juice.
Melissa,
Fred had a great response. very informative and well written.
I am suprised that no one has mentioned the size of your breaker panel. Depending on the age of your home, there are a lot of homes out there that are still using a 60 amp service that has not been upgraded to the standard 100 amp service. If you have to upgrade your service and you plan to stay where you at and continue woodworking, I would go to a 200 amp service if you can. What this allows you is more room for growth as you add new equipment the cost is not that much more to go to 200 amp vs. 100 amp. Or having to upgrade again down the road. As laxtase said grow into your equipment. At least I think it was Laxtase, under your Table Saw Diary.
I know that this may piss off some service techs to make this public. There are a lot of electricians, hvac, plumbers that use whats called Flat Rate pricing. Some will even show you a very well arranged book with all the prices listed. This pricing is great for the company but not for the consumer. I had a friend that was quoted $1200. for a job that wasn't worth $200.00 for a hours worth of work and about $50.00 worth of parts. When you get prices try to get at least three prices and have them break down the labor in hours and the material that will be used.
Figure out what you will be buying before you start running curcuits, find out what size breakers you will need. You don't want to run a machine that needs a 20 amp breaker off a 30 amp breaker because thats what you have. Make sure the breaker is what you need. Also a 20 amp cord should not fit into a 30 amp plug or a 50 amp. They all have different plugs, or put it this way they should have.
Truth be told it's not rocket science, just a lot of common sece and following the rules as written in the National Electrical Code.
I like to feel that there are more honest service companies out there than dishonset. But after more than 30 years in the trades I am ashamed of some of the things go on out there when it comes to pricing.
There is nothing wrong with a company making a profit. But I have not seen any company that uses the flat rate book not get greedy. It's looked at as a licence to steal.
Taigert
Update:
I installed the new breaker and 240V circuit myself. The electrician I had out quoted me $500, which is outrageous IMHO as the parts cost me $100 at home depot.
I read the code, and other than fighting with the stiffness of 10 gauge wire, it was easy.
Now, how to get a 600 lb saw into my basement .....
Melissa
like I said call around to gun shops & locksmiths to find out who they have move their safes. They are set up withn the proper set of toys for that sort of stuff, like stairs. The guy I use, when I last had him help me out in November when I moved into my new shop only charged me $275.00. And that was to move my big table saw with two tables, a 1200 lb 12 joiners, my 22-44 oscilating drum sander, full size mortising machine, 15" planer, 14" band saw, big drill press, scms, monster cyclone the 5 hp Shop fox its like 9' tall. The Cyclone rode on his lift gate, he ran out of room in his truck. Pete's normal area of work is the greater Cincinnati area, I am 50 miles west of Cincy. Thats a lot of work for the price sure he only moved my stuff 10 miles. But he had a 100 mile round trip of travel to get here, plus he has a helper with him all the time. I felt guilty and asked him if he was sure about the amount he was charging me, but he wouldn't take any more money. He says he makes a good living?
I originaly was put in contact with Pete through the Woodcraft store in Cincy. When I bought my new Unisaw last summer. I had him deliver the Unisaw from Woodcraft and make another p/u in Cincy for a drum sander, then a 50 mile drive to my place. All he charged was $200.00.
I don't know what a safe mover would charge in your area, but they can do the job. And the great thing is you don't have to worry about any one or any thing getting hurt.
Taigert
Which saw did you end up buying?????
Thanks Taigert, I am looking into gun safe movers.
I didn't buy a saw yet - want to have the moving plan in place first. I will probably buy the PM2000 from Woodwerks - I called and they said they would do residential delivery with lift gate for free (most other places I found charge at least $150 for that service, and a lift gate is not guaranteed!).
Anyway, I have scant hope that the movers will cost only $200. Everything here in Massachusetts seems to be about 5X the cost of anywhere else :(
cheers,
Melissa
A Powermatic please say it's
A Powermatic please say it's not so??????????
Did you look at the new Unisaw?
If your getting it from Woodwerks, are you getting the one with the good motor made in the USA, and the cast side table with the fancy paint job?
I like the one with the flames rolling up the sides.
Taigert
Taigert,
Was that thump I just heard you falling out of your chair?
I hope no one was asleep in your house when you yelled out, "POWERMATIC!??"
--jonnieboy
Just thought I'd let y'all
Just thought I'd let y'all know. Indeed it is a powermatic 2000 that I settled on. Yippee! Can't wait.
Sorry Taigert. ;-)
~Melissa
MG,
Ahh, a new saw on the horizon. That's great.
I wanted to get back to your shop wiring for just a bit. What size is the main breaker in your electrical panel? And, how many more slots do you have open?
--jonnieboy
Jonnie,
My main breaker is 100A. There are 6 slots still open after I put in the new double-pole.
I used a 30A breaker/wire/receptacle. The saw (at 240V) will be rated for more like 13A, but I guess I just wanted everything nice and beefy. I've decided to put a 2nd receptacle on this same circuit for a dust collector. Once that's done, that should be all the electrical I'll ever need for the shop!
MGM
mg,
Wow, six open slots in a panel is great.
I'm also curious, is the panel set into a wall and surrounded by sheetrock, or is it exposed as it would be in an unfinished basement? The reason I'm asking is to determine the ease of getting wires for new cirucits into the panel.
Even though you think this 220v circuit is all you'll need, it's probably not. You'd be surprised. I was surprised.
I'm only saying this so that you think about how you'll address future wiring needs. That is, if you find the need to do so.
Sub-feeder panels themselves are fairly cheap, and they often come with breakers. I think I paid less than $50 for a 100A, 20 circuit panel and it came with the main 100A breaker and five branch-feeder breakers.
It's the installation that's expensive. I'm guessing again here, but judging from what you've already done, and the fact you're some type of engineer (I.e., likely to have at least some mechanical intelligence), you seem capable of doing the wiring out of the sub-feeder panel on your own, or with some pointers from people who know how to do such work safely.
I saved a lot of money by doing all the work myself after I paid an electrician to tell me exactly what I needed. This was after I'd already run two or three circuits at a time into the existing panel. I then had to re-route those cables and put them into the new sub-feeder panel. That was extra time and cost in materials. I wish now that I'd installed the sub-feeder to start with. Then I could have added circuits and wiring as the need arose.
These are just some thoughts from my experience. You'll have your own experience and circumstances.
Definitely and always, go for answers to a qualified person, and don't ever work on live circuits.
Let us know how the saw adventure goes!
--jonnieboy
mg,
Not to pound the subject to death, but I was just re-reading Taigert's post above, and he had some really good points. In particular, with a 100A main panel you might be limited as to the size of sub-feeder panel you can install.
This falls under the heading of asking for competent advice at the outset. We've all said it enough that you know to do that.
-jonnieboy
Hey guys,
I appreciate the advice. I may be eating these words in the future, but I honestly can't imagine a situation where I'd be running more than 1 big machine and 1 dust collector (and my dehumidifier, ... and shop tunes) at once. Okay, I see your point :-)
However, my thinking is with the 240V equip the big machines will draw less current overall, giving me more headroom in my 100A system.
With 6 open breaker slots that's 3 new 240V circuits if I want it.
I just can't imagine needing more??
----
My breaker box is in an unfinished basement. It's really easy to get to, as these things go.
----
I am actually an electrical engineer ;-) I am kinda ashamed to admit it since here I am asking for electrical advice!, but I spend my days designing 3V / milli-amp chips. 240V - the theory is the same, but bottom line is, it is new stuff to me (and I respect that kinda power).
cheers,
Melissa
Melissa, Unless your crystal ball works better than mine I'd put in just the circuits you need right now and save the rest of the work for later. I put in my own 220V line for my Grizzly TS and years later, haven't had any need for any more. Of course, my situation isn't like yours so more than one circuit may be a good idea.
Pulling the cable and doing the connections at the receptacle is pretty easy - common sense type stuff for this mechanical engineer - so I'm sure you can do it. I don't mind working inside the sub-panel either but I'm VERY careful the power to it is cut and no one else is around who will turn it back on again until I'm done. Doing the prep work and hiring an electrician to do the panel work should cost you the minimum charge, as long as everything is prepped correctly. Doing a panel hookup and inserting a breaker takes about 30 minutes for an amateur like me.
Good luck!
mg,
Hey, since you have an exposed panel, and they're so easy to get cables into, there's no need to even think about it further right now, if ever.
Didn't mean to belabor the point.
--jonnieboy
M,
It's not a good idea to
M,
It's not a good idea to "upgrade" a circuit breaker to 30A, when the machine max load is 20A. Should a fault occur, your breaker will happily put out 20-30A all day which can start a fire on 12awg wiring. You want the breaker to trip during an actual fault.
As far as 220-240V service goes, yout panel may already have two 120V phases. Every other breaker slot uses the other 120V phase. A 220-240V breaker taps both 120V phases to produce 240V. Be sure you don't need a neutral wire and you can use exissing 12 gauge wires. ALWAYS use the safety ground.
As I am typing this, it occurs to me that you should hire a professional, licensed electrician. Don't be a cheapskate and burn your shop down!
C11
Hi Melissa, as an Master Electrician, with 35 years experience, I have read some of these posts,and, quite frankly, most are complete idiots.All you want is a circuit which will supply you adequate power for new machine tools. A 220V circuit run to a machine means a better supply of energy vs. a 110V source which is not balanced. A 20A 220V circuit has the capacity to run a 3 HP motor easily on 12 gage wiring. ( 12 AWG--isulation type THWN rated at 30A--not 20A) -- a horsepower is equal to 750 watts--fairly simple to run X amount of distance for pipe/cable for 220V wiring, a 2 pole 20A breaker, cost about $20 average, to a receptacle in a outlet box, about $10, and a 12AWG cord with apporpiate cord-caps 25' long, say $25 and the correct cord-cap on your machine. Add in the amount of time needed---installation costs ofthe cable/pipe/wiring varies with the distance and weather it it through a wall/ceiling/floor or outside underground or mounted on walls. ALSO., get a permit from the local city/county inspectors which provide you with a quality control, and a reference for any insurance/warranty needs.
220v X 20A== 4400 watts 3 HP @ 750 watts per HP===2250 watts even allowing 125% of load for the motor-start which is approx. 2800 watts--you have substancial capacity for many tools. Good luck and happy sawing/planing/jointing/sanding!
Quixdraw,
Way to jump in a month after the fact and call those with well-meaning advice idiots.
You well know that responses here are of the pick-and-choose variety, a point in the right direction.
Many of the replies here advise to refer questions and work and to a qualified electrician.
-jonnieboy
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