Another 3 phase question

[MIKE NOAH]

After browsing one of the local salvage building centers that deal mostly with damaged freight a 20 in disc sander followed me home today. This unit is new but had been knocked over. I have been staring at this unit for over 8 months everytime I went in the store and even went to the trouble of looking up the cost of replacement parts. That's when I realized it was a 3 phase model (the rating plate wasn't visable at the time) and had pretty much lost interest in it as a result. Well the owner of the store kept on me for an offer and I made one, opps, on the trailer it went. The motor doesn't appear to be damaged at all, most of the 397 lbs falling over broke small cast pieces and a handwheel.
So here's my dilemma,
The unit is a PM DS20 3hp 3ph 9.8amps(IIRC) unit
Do I need a static phase converter, a rotary phase converter? Or since I am 3 ph challenged just buy WHM's replacement motor for their 2hp single phase DS20. Do I see myself requiring more 3 ph down the road?:no::dontknow: I quess never say never something else might follow me home.
Not matter what I do I think I'll come out okay money wise, well less than half price of a new unit. But it might spend a lil more time collecting dust rather than making it while I save up for a motor or converter.

If so all/any suggestions would be greatly appreciated.
Thanks,
Mike

 

[tjgreen]

I am so not an expert on this - never done it, so hopefully someone with more experience will weigh in. The disclaimer out of the way: I looked into 3ph a couple years back due to an awesome deal (someone else got there while I was dithering). Basically, here's what I found out. Static phase converters are usually cheaper, but they also don't allow the motor to run at full capacity since they only deliver 3 ph at startup; after that, single phase, so no more than 2/3 of rated HP, less if you've got a Delta wound motor (or not at all, depending on the converter). They can also wear out faster, so might need replacing. A rotary phase converter delivers 3 phases, so your motor will run at full capacity, and will last longer, but is significantly more expensive. If you're somewhat comfortable with electrical work, I also found sites with instructions on building your own converter for a lot less - just google building a phase converter.

A friend at work has actually built one, and is super-helpful; if you want, I'd be happy to ask him for more info.

Good luck.

 

[scsmith42]

Bernhard, you're a man of few words... :rotflm:

Mike, check into a variable frequency drive - it may be the most cost effective solution for you. Jeremy (Woodwrangler) has one on his big bandsaw.

Scott