Replies

1. 
   wcperry4 | Jan 19, 2003 04:58pm | #1

   Personally I'd call in the cavalry.  I recently had the wiring upgraded in my garage to 220.  I did the grunt work (dug a 36inch deep trench from my house to the garage) but had a certified electrician do the technical stuff.  He did a beautiful job and I've never had a moment of doubt concerning the safety of it all.  You're talking about some hefty wiring there.  I'd go with a pro.

2. 
   krumy1 | Jan 19, 2003 05:02pm | #2

   Unless your area of the country is much different than mine it may be difficult to get 3 phase to a residence. I can't imagine that you already have it in your panel. Check with your power company before you buy the saw as you're probably looking at major expense if it's even available.

   Steve K

3. 
   BOBABEUI | Jan 19, 2003 05:14pm | #3

   Hum.. 3 Phase power, I would give most anything the old college try once.. But in this case I think I would punt and call in the electrican

4. 
   TKanzler | Jan 19, 2003 05:58pm | #4

   Are you sure that motor is 3-phase?  If it is, you are almost certainly SOL.  Unless you live in a converted industrial building, you won't have 3-phase available.  You can run that saw on single-phase with a static phase converter (giving you 2/3 of 5 hp =3.33 hp), and probably use the existing motor control, or you can buy a rotary phase converter, which will yield full power.  Static phase converters are relatively cheap.  Rotary converters use an idler motor (acting as a transformer, and recommended to be 2 to 3 times the hp of the load motor for full output, or the manufactured leg will be weak), and will be costly for the 5 hp motor you want to drive.  You can also make your own, using a static converter and an idler motor.  This is const effective if you already have a larger 3-phase motor laying around.  Either way, your motor will have to be configurable for 230V operation.  Check yours; it may be 575V, in which case you have no choice but to replace the motor (you don't want to add in the cost of a transformer).  The cheapest option is probably to simply replace the motor.  A new 3 hp will be quite a bit less costly than a new 5 hp.  Your local motor shop may even have a used or rebuilt C-face motor.  I'm usually the last one to suggest not trying something yourself, but in this case, I'd suggest you consult an electrician and a motor shop.

   http://www.phaseconverter.com/         http://www.phase-a-matic.com/

   Be seeing you...

5. 
   jgaiennie | Jan 19, 2003 05:59pm | #5

   It's almost certain that you don't have 3 phase power to your house.  Further, it my not even be available on the pole / transformer.  If you have an overhead line near your house, you can look at it an tell if 3 phase is there.  Typically, there are three main conductors all at the same level near the top of the pole on a cross bar, with a single, smaller conductor attached to the top of the pole above the cross bar.  Now getting that power to your shop may present some challenges.  Surely your first call should be to your power company and the next to an electrician.

   But I think you don't need to do all that.  You can buy a phase converter, a gizmo of which I'm no expert.  It's my understanding that these devices have improved in recent years to make setting up a three phase tool a single phase environment real viable option.  Do a search on the web.  Check the woodworking mags for articles.  I'm sure I saw an article some where just very recently (that I did not read) about these.  I think you're talking in the neighborhood of $250.00, but I'm probably wrong.

   Another option you may want to consider:  Perhaps you can replace the motor or maybe even have it re-wound for a few hundred bucks.  If you're talking about a great old heavy tool that's in good shape and worth a couple of thousand, you just may want to look at those options.

   jdg

1. 
   riverr1 | Jan 20, 2003 03:39am | #6

   I have some power issues in my shop involving 3 phase and while dealing with this Edison disussed something I didn't know to see if it 3 phase is available or not. --Just another way to tell and may not be the same everywhere.--

   3 phase needs two transfomers on the pole. These don't necessarily need to be on the same pole, but they will be on opposite sides of the pole. So, if you look down the line and you see 2 transformers on opposite sides of the pole, 3 phase is at least available. If you don't see two transfomers that does not necessarily mean that it isn't available. Another transformer needs to be put in. Here it cost $7.50 per KW. A minimum of a 75KW transformer is needed. Funny how those numbers match! You will also need to pay for the line at up to $4.00 a foot.

   As most have stated though, 3 phase power is a zoning issue. About the only way to get it around here is as a minimum of a light industrial area and up or some HVAC issues in nonindustrial but still commercial situations. Beyond that farmers can get it--mostly dairy farmers here as irrigation is not the issue it is elsewhere.

   I learned all this while dealing with getting power to my shop and discovering what power I had. Neither Edison or city knew the pole my power comes off of even existed anymore. Long interesting story here, but not pertinent. Good luck.

   Don

6. 
   WoodChuc1 | Jan 20, 2003 07:55am | #7

   A quick way of checking to see if you have three phase power on your street,is to go and look at the wires at the very top of your telephone pole. Unless there are three wires up there you are out of luck,if there is three wires then you can get three phase to your house. Even if you did have three phase on the street,it wouldn't be worth bringing it to your house, unless you have a lot of money to burn! Your only other option is to get a phase converter.

   Bill Bleiler

1. 
   bobhallsr | Jan 20, 2003 09:39am | #8

   There is one option which has not been discused and that is the use of a Variable Frequency Drive to provid 3 phase power from single phase source.  I would expect that you can buy a 5hp VFD on eBay for about $300.  I think that is cheaper than replacing the motor.  (I believe that the Powermatic moter case is not standard)  At start up the VFD ramps up the cycles from 0 to 60 cycles so that you get a soft start.  When you turn it off the VFD uses the motor's inductance to brake the saw very quickly.  If the 3 phase tool has been deep discounted you may be able to buy a VFD for it and still come out money ahead.  Don't turn down a 3 phase bargan until you check eBay for a VFD to match it.

   Get an electician qualified for wiring controls for this job.

   BJGardening, cooking and woodworking in Southern Maryland

1. 
   jgaiennie | Jan 20, 2003 02:48pm | #9

   Bee Jay,

   Does the VFD perform the phase conversion to convert single phase to three phase? 

   jdg

1. 
   RickL | Jul 30, 2004 07:25pm | #11

   VFD - Variable Frequency Driver: This is an electronic circuit - an inverter actually – that converts single phase AC to DC, and then to 3 phase AC.

   http://www.deselectric.com

7. 
   jasoutside | Jan 20, 2003 03:01pm | #10

   Hey All,  Thanks for all the great advice!  I believe that I might just shy away from the phase 3 stuff.  I may not be long for the house I am currently living in and I'd hate to spend all the resourses to upgrade only to move into the same problem.  It is also pretty hard to justify such an expensive saw for me right now let alone the potentially expensive upgrade.  Thanks again you guys!!

1. 
   RickL | Jul 30, 2004 07:31pm | #12

   I'd put a static on the saw. Not that expensive and no need to worry about transformers on the pole. I agree with Tom and his speculations.

   http://www.deselectric.com/price