The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Correct rotation, wrong sequence
by Potseal
Yesterday at 03:14 PM
Industrail Control Panel bonding per 409.108
by sparkyinak
12/09/16 06:29 PM
Calling all Non-US members!! (Non-US only)
by aussie240
12/07/16 02:39 AM
Photo Upload Tutorial
by DanK
12/06/16 11:35 PM
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
HotLine1 9
Potseal 9
sparkyinak 8
Texas_Ranger 7
Who's Online
0 registered (), 8 Guests and 1 Spider online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#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.

Thanks

Dick in San Diego

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

Member

Registered: 04/03/02
Posts: 6805
Loc: Brick, NJ USA
Niki:
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.
_________________________
John

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals