Fairbanks Morse motor

benchracer1 · Aug 29, 2021

I have a tree 2uvr mill with the Fairbanks morse motor for the power feed. It is stamped 3 phase on the data plate but only has 2 wires going to it. When I start the motor it hums until I give it a spin by hand then runs fine. I thought three phase required three wires. Anybody got any ideas on the start issue?....Steve

TGTool · Aug 29, 2021

Just a guess that a previous owner didn't have 3 phase. If you want correct running you'll have to dig in and find the third connection and supply it with the juice it needs.

The behavior you see is exactly what you'd expect from a 3 phase motor on one phase. There's no initial rotational torque to get it up to speed unless you mechanically supply it.

deltap · Aug 29, 2021

2 wires it ain't 3 phase. A single phase motor with a bad end switch or start cap will do that. How do you change feed rate with ac one speed motor?

GregSY · Aug 29, 2021

Yep. It's missing a lead.

benchracer1 · Aug 29, 2021

I'll try and post a couple pics tomorrow. The outside of motor is definitely stamped as 3 phase. There's 3 wires coming into the on off switch to terminals l1 l2 and l3. Outbound from the switch there is t1 and t3. There is no t2 to be found.

benchracer1 · Aug 30, 2021

Thanx guys. Sure as hell a missing lead. I installed one and problem solved. I have no idea why it was gone

Search

Largest Manufacturing Technology Community on the Web

Search

Fairbanks Morse motor

benchracer1

Aluminum

TGTool

Titanium

deltap

Cast Iron

GregSY

Diamond

benchracer1

Aluminum

benchracer1

Aluminum

Similar threads