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Brown & Sharpe #2 surface grinder really 2 phase ?

Overland

Stainless
Joined
Nov 19, 2017
Location
Greenville, SC
Well I just picked one up from a sale. Looking at machine label I see "2 phase".
Strange.
On the old GE motor label "2 phase".
I've never heard of this before.
I normally run 3 phase machines off a VFD as I only have single phase.
Can I run this off a VFD, does anyone know ?
Or any other ideas, please.
Thanks,
Bob
 
Niagara Falls supplied it to Buffalo.
25Hz too.
Add a start cap and a current relay.
Most single phase cap start motors are
really 90° 2 phase motors. Surprise !

--Doozer
 
The machine came from Reading PA.
The shop has 430 volt supply and they used a transformer, down to 230 volts.
I didn't realize it was a 2 phase motor when I picked it up.

I'm not getting what you guys are saying about running motor off 230 volts single phase.
Could somebody spell it out for me, please ?
 
If you want to enough, or happen to have the transformers laying around, you can hook up the classic "Scott" connection and give it 2 phase power.

Be the only one in town with real 2 phase power!
 
For Scott connection you will need 3 phase. 2 phase power was used quite a bit in the big cities. I lived in NJ and many machines that came from Paterson, Newark, NYC and many others as well as those mentioned had 2 phase motors. At one time 2 phase motor were all over the place now they are hard to find. I did get them to run on single phase with an RPC but been so long I don't remember how. As mentioned previously your best way is to swap the motor with a single phase motor if it's belt drive. 2 phase is a 4 wire motor, you will need 4 wire supply. VFD has only 3.
 
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Reggae,
I tried to Google running 2 phase motor off single, but no useful results.
Could you spell out for me what you're saying with capacitors and so on please ?
Bob
 
Reggae,
I tried to Google running 2 phase motor off single, but no useful results.
Could you spell out for me what you're saying with capacitors and so on please ?
Bob

I will have to check my one and only 2ph machine and get back to you. At work now.
There are also some previous discussions and solutions posted here. Might be able to provide that more quickly.
 
VFD and a Scott-T transformer arrangement if the motor has historical/antique/aesthetic value for a home shop installation. Otherwise swap it.
 
VFD and a Scott-T transformer arrangement if the motor has historical/antique/aesthetic value for a home shop installation. Otherwise swap it.

No, there is no need.
Scott-T transformers aren't cheap although it's been explained that you can you use a simple center tapped and get "close".
This is for a surface grinder, can't substitute any old wash machine motor and be fine.
 
Froneck;3815949........................ 2 phase is a 4 wire motor said:
Motor has two coil sets, but can be wired 3 or 4 wire, usually, depending on what you have available as a source. Either way it is still 90 deg phase difference.

A 3 wire motor is harder to use with 4 wire power than the 4 wire motor is to set up for 3 wire.

VFD by itself is not much help since it produces 3 phase unless reprogrammed significantly.
 
Yes I know 2 phase motors have 2 soil sets yes 2 can be commoner, I do remembering connecting wires together when I adapted 2 phase motors to on on single phase power. Was about 50 years ago. Kinda forgot what I did! Machinery was really cheap when on auction they were found to have 2 phase motors and where I lived NYC and Philadelphia were about the same distance, little over hour drive. Dealers stayed away from 2 phase machinery as well as the average shop owner. I could get them cheap and sell them to guys with small shops though I don't remember converting any that had larger than 10HP motors. From what I have read Tesla's first few 2 phase alternators were actually 2 single phase Alternators coupled 90° apart.
 








 
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