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#207019 - 09/14/12 04:44 PM 3 phase motor questions
niki Offline
New Member

Registered: 09/12/12
Posts: 1
Loc: san diego,, CA
Hello. I hope that this is the right place for this, but I need some help with a 3 phase motor. I am a glass artist, and have a polishing lathe that is a 5 hp, 3 phase motor turning a spindle on bearings. I have several issues. First, I do not have three phase at my home studio, so got a rotary phase converter. It runs two pieces of equipment for me. After running the lathe for 30 minutes, the shaft at the bearings heats up an awful lot. My infrared only says 130 but it feels hotter than that. It is well greased. When it is not running the voltage is as follows:

a-b 221
a-c 224
b-c 241

on running:

a-b 209
a-c 215
b-c 221

Is that alright, and what should I do if anything about the shaft heat?

Second to that, is there anyway to add speed control to this without reworking the pulleys? The belt is around the shaft, and encased in a cabinet, so I don't know how to adapt that.


Dick in San Diego

#207024 - 09/14/12 05:50 PM Re: 3 phase motor questions [Re: niki]
HotLine1 Offline


Registered: 04/03/02
Posts: 6792
Loc: Brick, NJ USA
The advice I will give you is to consult a local licensed electrical contractor to check your installation.

The forums are not intended to provide 'how to' guidance to DIY people.

This thread is being locked.


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