Replies

1. 
   nikkiwood | Aug 06, 2004 08:39am | #1

   I am no electrician either, but I did this recently, and there was diagram right on the motor housing.

   You might have a look (on the outside), and if not there, take off the motor cover, and you might find it inside.

1. 
   CharlieD | Aug 06, 2004 08:59am | #2

   On my way to the shop...

   ...

   ...and Splintie is the winner! It was right on the motor. I find it fascinating that the wiring for 220 was actually a simpler setup than the wiring for 110; 220 uses 3 wires, 110 uses 6. Anybody know why that is? What's inside that motor? A very easy change, overall. Took less than 5 minutes.

   Gotta go tomorrow and get a proper plug for the end of the power cable. Can't wait to try it out.

   Thanks, Splintie.

   Charlie

   I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

1. 
   TKanzler | Aug 06, 2004 06:58pm | #3

   Hopefully, you used all 6 leads for 240V operation, too.  Three of them get tied together, and the other three connect to the mains (2 on L1, 1 on L2). 

   There are three windings inside a dual-voltage single-phase motor.  Two are main windings, the other is the start winding.  At 240V, the main windings are connected in series, and the start winding is in parallel with one of the main windings.  So there is a main and a start winding lead connected to L1, and the other main winding lead connects to L2.  The other three leads connect to each other.

   At 120V, all three windings are connected in parallel, so three leads connect to each of the mains leads (L1 and L2).

   Here's a PDF file from Baldor which should help you see what's going on inside a single-phase, capacitor-start, reversible, dual-voltage motor.  Three-phase dual-voltage motors are similar, except that there are 6 main windings (2 for each phase) that can be connected either in series or parallel.

   http://www.baldor.com/products/drawing_files/pdf/CD0001.pdfBe seeing you...

1. 
   CharlieD | Aug 06, 2004 07:23pm | #4

   Well, I did do that, but not because I unerstood it, that's for sure. I just followed the diagram. I do now though; prior to your explanation, I couldn't figure how three wires not connected to any line source could have any effect. I get it now though, cool. Figuring out 220V service was a similar enlightening process.

   Delta even supplied a spare wire nut inside the wiring housing.

   Electricity is pretty amazing, or rather, the ways that folks have figured out to make it work are amazing.

   Thanks so much.

   Charlie

   I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

1. 
   bones | Aug 07, 2004 04:36am | #12

   Go by Books-a-million or B&N and get  "The ultimate guide to table saws".  It is put out by Popular woodworking magazine and it will be with the magazines. It's been out for a while, but I still see it, so they have not pulled it.  It has an excellent article about this subject on pg 31-35.  It is titled "The truth: 240V is Better".  If you cannot find it, send me an E-mail, and I'll scan it for you and e-mail those three pages(that is if no one threatens to sue me). 

2. 
   CharlieD | Aug 07, 2004 06:35am | #13

   Wow. Well, I'm leaving town for 10 days Monday am, so I won't be able to get to a book store; but you have my interest. What was the gist of the article? Why is 240V better?

   Charlie

   I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

3. 
   bones | Aug 07, 2004 08:24pm | #17

   It's a magazine, so don't look for a book by the title I mentioned. I scaned it, but there is no way to attach it in an E-mail to you. It's a 1.7meg pdf.

   Here is the main gist of the article mostly Verbatim.

   "Myths:

   You will not save a watt of energy or a single dime by switching to 240v. Whether you're running a motor using 120v or 240v, the horsepower of the motor stays the same. Remember: one horsepower equals 746 watts, and watts = volts x amps. If your volts go up, your amps go down. If your volts go down your amps go up. (Watts always stay the same.) The utility company charges you for the number of kilowatt hours you use- not amps or volts.  Whether you're running a motor using 120v or 240v, the motor's revolutions per minute will stay the same.

   240 is better because you evenly distribute the load across both the buss bars in your panel (each ~ 120v). By doing this you help prevent drawing too much from one leg and creating a sag.  The next big reason for 240 is heat. Reduced current flow creates less heat. Heat is a motor's deadliest enemy. A common rule of thumb in the motor industry is that a sustained temperature rise of 18 degrees Fahrenheit in the windings of a motor will cut the rated motor life in half."   

   There are other more details in the article and lots of helpful diagrams.  The article is written by Kara Gebhart & Greg Hyland. The whole issue of this magazine was very helpful, and I would recommend it. 

   http://www.popularwoodworking.com/store/backissue.asp?issuedate=7/1/2004

   The back issue price is $7.00. It's still at BAM for $4.99.

   Edited 8/7/2004 2:03 pm ET by bones

2. 
   forestgirl | Aug 06, 2004 07:32pm | #6

   Thanks for the info and the Baldor link.  I've printed them out for that wonderful day when my shop has a 220 outlet.  (Have the service at the panel, just haven't gotten an outlet in yet, LOL!)forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

1. 
   TKanzler | Aug 06, 2004 07:44pm | #7

   FG- For what it's worth, virtually all dual-voltage, reversible motors are wired this way.  But you may find spade lugs, or ring terminals on posts, both with color-coded leads, or even little metal jumper bars on numbered terminal posts that you move between posts to change rotation or voltage.  Baldor uses loose, numbered wires, but you're likely to find anything on another company's motor.  Point being, the appearance may differ, but they all work the same way internally. 

   And keeping the sketch is a good idea, as it can help you trouble-shoot motor problems if you have an ohmmeter (look for the same DC resistance across each main winding, and no continuity between them, with all leads disconnected).Be seeing you...

2. 
   CharlieD | Aug 06, 2004 10:10pm | #8

   I'm interested in how performance might change; I've gotten different answers. Some say not at all, some have said it'll be a significant improvement but couldn't elaborate. What advantage is there other than cutting the amps in half?

   CharlieI tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

3. 
   JohnWW | Aug 06, 2004 11:34pm | #10

   If the 110 volt circuit was adequate for the load, with properly sized wire and not too much already being drawn off the circuit by other equipment, there would be no obvious difference when you switched to 220 volt.  If the 110 volt circuit was marginal, then you will find that the saw will start and run better on 220 volts.

   John W.

4. 
   Michmesquite | Aug 07, 2004 04:07am | #11

   Charlie

   I gotta agree with JohnW on this one. If it is working fine with a good 12AWG circuit running from a sub-paneled 20A Breaker - Why fix it._________________________________

   Michael in San Jose

   "In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted." Bertrand Russell 

5. 
   CharlieD | Aug 06, 2004 10:16pm | #9

   FG, have you got a subpanel in your shop, or how is the 240V available? Wiring for 240 isn't harder than 110, but I nearly caused a real problem getting the service to my shop. I thought I understood it, I really did; it's just 2 110 volt lines summed, or so I thought. WRONG, it's 2 110V lines 180 degrees out of phase, feeding to each other through the circuit (if I now understand it correctly, Tom can correct me if not.) Easy enough, as long as you get it. I'm doing new work, having framed up a room in the garage, that makes it even easier.

   CharlieI tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

6. 
   forestgirl | Aug 07, 2004 07:52am | #15

   Nick (hubby) had the panel up-graded several years and and had a 220 line put in (sorry, might not be technically right, LOL).  The 220 circuit leaves the sub-panel and goes to a closed-off box a couple feet away (an outlet box with no outlet, sorta).  I need to go from that box out another 6 feet or so and put the 220 further down the wall.  I've looked at pictures in an electrical book, but haven't felt totally confident about putting in the box myself.  I could be convinced though......am going to run out of amps pretty soon.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)Another proud member of the  "I Rocked With ToolDoc Club" .... :>) 

7. 
   CharlieD | Aug 07, 2004 09:00am | #16

   Well, now in that case, it may indeed be useful. Half the amps if you double the voltage (roughly.) Plus, you've added another circuit; othjer tools (i.e., a dust collector) may be using a 110 circuit while your TS or BS could be running 220. Your Grizzly BS will wire for 220, yes?

   In any case, I'm going to try it out, why not?

   Wiring for 220 isn't really hard; there are two supply lines to your panel; you use a "twinned" breaker--that's what the electrician that hooked up our new AC called it--that connects to both of these supply lines. Then it wires very much like a 120V line, but you have to remember that there is no nuetral. There are instead 2 hots, and while one pushes, the other pulls, 60 times/second. That's how the voltage is doubled. An analogy was made to a single lumberjack (120) using a crosscut saw, vs a pair of lumberjacks (240); one pushes, the other pulls, doubling the power. But I initially misunderstood this, and thought that there were twice the hot wires and still a nuetral to complete the circuit. Nearly blew my face off, or so it felt. Those 2 hot lines must not touch each other; to do so (which I did) is exactly twice as bad as a 120V dead short. Egad, and never again. I melted one of the lugs in my new subpanel to magma.

   Charlie

   I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

8. 
   CharlieD | Aug 07, 2004 07:51am | #14

   Well, an online search didn't turn up Bones' article, but there was an interesting posting of letters in response to that article, and the reason I repied to FG to post this is that in a reply to one of those letters, an editor of the mag contacted Delta who assured that there would be no noticable improvement in performance w/a change to 240V. FG, I'm not sure it's worth bothering to add that 240V circuit. Here's a link, if I can make it work (I almost never can. I'm not an idiot, really, I just can't make these things go.)

   http://www.popularwoodworking.com/features/240V.html

   Charlie

   I tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

2. 
   splintergroupie | Aug 07, 2004 10:39pm | #18

   Hiya, Charlie. The mistaken identity flatters me, but credit should go where credit is due: the props are to nikkiwood.

   Splintie

1. 
   CharlieD | Aug 07, 2004 11:07pm | #19

   I'm really not an idiot (at least I don't think I am...hmm...)

   Thanks, sorry, etc.

   CharlieI tell you, we are here to fart around, and don't let anybody tell you different. --K Vonnegut

2. 
   bones | Aug 06, 2004 07:30pm | #5

   CharlieD, look on the motor housing. Generally the diagram is there & shows how to change the wiring to run at 220. If you have the owners manual it should have a wiring schematic in the back.