Replies

1. 
   RW | Oct 16, 2002 07:16pm | #1

   DK what your options in the building look like but 3 ph motors are the cats meow.  Might as well get the panel in while things are empty and you'll have your regular 110 to start with. As you buy new tools or replace existing motors, you can just tie in to the panel as needed. 3ph is kind of like buying your first air tool. "I'll only ever really need a compressor for this little brad nailer . . . " then two years later DeVilbiss is sending you frequent flyer miles. Had the opportunity to buy a shaper table once for a heck of a bargain, but it was 480/3 and I passed. I still think of it sometimes. *sniff*

2. 
   PlaneWood | Oct 16, 2002 07:17pm | #2

   Don -

   This going to be a commercial shop or hobby shop?

   I would bring 3 phase in to a box for now.  That way you will later have the option of 3 phase or single phase when buying tools.  I think 5 HP is a good starting point for 3 phase.  With 5 hp your drawing ~20 amps, single phase 220V.  That's starting to cause quite a bit of resistance loss (more heating).  With 3 phase 220V you'd be drawing about 8 amps RMS per phase. 

   Hope my math is right - been a long time since I've messed with 3 phase.

   PlaneWood by Mike_in_Katy
   PlaneWood

3. 
   CRAIGCONEY_M | Oct 16, 2002 07:36pm | #3

   Don,

   By all means, have the 3 phase installed.  You can pull single phase off of the same panel in your shop.  You will find that even if you don't have a use for 3ph now, it will open up alot of opportunities for you in the future for machines, as well as save you on operating costs of AC if you ever need it. 

1. 
   DennisS | Oct 17, 2002 10:39pm | #6

   Since it relates to the subject line but not the initial question I trust it will be OK to as a sidebar question.

   Given a one person hobby shop with the usual assortment of power tools plus a 220 stick and 120 wire feed welder, what would be suggested for the min. size branch circuit panel capacity? Few if any of the big tools will be running at the same time.

   I'm figuring on a 100amp sub feed from the house panel - which has adequate capacity.

   Dennis in Bellevue WA

   [email protected]

1. 
   riverr1 | Oct 17, 2002 11:15pm | #7

   Dennis,

   Why 100 when you could have 1000? The real answer is based on the number of christmas lights you put on your shop! I miss Tim "The Tool Man" Taylor! lol

   Don

1. 
   DennisS | Oct 17, 2002 11:41pm | #9

   Christmas lights??!! Bah-humbug. Total waste of electricity that could be used for running WW machinery.

   1000amps? I've got landscaping over my eletrical service. I could probably move it to under the driveway and not have to worry about snow melting or thawing ice in the winter.

   Dennis in Bellevue WA

   [email protected]

2. 
   LeeEschen | Oct 17, 2002 11:40pm | #8

   Go for all you can get, Dennis. You don't know how your needs will increase in the future. You might install a lathe to turn 30 foot diameter bowls for hot tubs.

   --

   Lee in Cave Junction, Oregon

   On the Redwood Highway

1. 
   DennisS | Oct 17, 2002 11:43pm | #10

   30' diamter bowls? Now that's some hot tub!! Odd that you mention that though since I have a whole bunch of gorgeous redwood from an old hot tub that I'm gonna turn into a sink and vanity top.

   .....some day....

   Dennis in Bellevue WA

   [email protected]

4. 
   TKanzler | Oct 16, 2002 08:24pm | #4

   Out of curiosity, what is the nominal voltage available?  240, 480, maybe 208Y/120?  You'll need a transformer to get 120/240 single phase for lights and receptacles from the first two.  Not all motors are rated to work with 208V single- or 3-phase.  And do be aware that some power companies will charge lots (one-time and monthly) for 3-phase.  This subject came up recently on another forum, maybe Breaktime, and that last bit about access cost is what I remember some of the sparkies cautioning about.  Make sure you know what the costs will be ahead of time.  But on the plus side, motors are significantly less expensive and simpler (no start circuitry), and used WW machines with 3-phase are less desireable by home shop folks (hence cheaper than equivalent single-phase).  I've gotten really good deals (some were steals) on used 3-phase stuff, but I use a home-made rotary phase converter to roll my own 3-phase.  I don't want to be a wet blanket, but investigate costs first.

   Be seeing you...

   
   

   ---

   Edited 10/16/2002 2:49:08 PM ET by TDKPE

1. 
   riverr1 | Oct 16, 2002 10:59pm | #5

   Thank you all. A lot of stuff here I wasn't aware of. I was still getting over the last power plan for another shop when this one came up. I will use the shop for my business, but I always have and never had 3 phase in this area. Hadn't considered the costs. Had 3 phase in the back woods of Florida many moons ago and there was no difference in initial costs. This building was built as a blacksmith shop many moons ago. At some point it became a custom automotive radiator shop, but has been closed for many years and has been a storage building. I can see from the old panel that 440 was available at one time. I imagine for a welder. Thanks again.

   Don