[Newbie] White Smoke From New To Me Mill Motor

[minions]

How did you check? A "static converter" does not generate three-phase power. What it actually does is convert the motor it is connected to into a capacitor-run single-phase motor. There's nothing in there but some capacitors and a relay. It's possible that the start relay in the converter is stuck, though. A failed start cap would not cause the motor to run smoothly but overheat. Regardless, a motor that has had smoke come out of it needs to be inspected.

Thanks for the info, I didn't know that. I checked the ac voltage between the 3 legs, one read 0, so phase converter may be working okay.

 

[minions]

In my experience, I have had two SPC’s fail on me. Both due to the resistor in them. The caps and relay were good. It’s an easy one to trouble shoot and fix. The resistor will look fried. I changed them to a higher watt rating and all has be good. But a VFD is a much better 3ph option…Dave.

Resister looked okay, I'll check it again when I get home. I think I'll buy another 3 phase motor and replace. now the VFD, is that a separate unit that I buy or does the motor come with it installed? I'm new to all this. can I just buy any compatible 3phase motor now and install VFD later?

 

[John Hasler]

I checked the ac voltage between the 3 legs, on read 0, so phase converter may be working okay.

With the motor connected and running you should have voltage between all three legs. With the motor disconnected but the converter on you might read zero on one pair depending on the design but that does not tell you that the converter is ok. You shouldn't power up that motor until it has been inspected, though.

 

[Bob Korves]

Not just any motor will fit on your Bridgeport and do what it needs to do. The ones that do fit can be expensive. The first thing to do is to take the motor off the machine, and take it and the phase converter to a motor shop. They can tell you in a few minutes where your problem(s) is (are).

 

[silence dogood]

The start and, if it has one, run capacitors will age even when not used. Ten years is a long time for those buggers. Take apart the motor and your converter and look at the caps. If the caps looks swelled and/or cracked, replace. While you are about it, check for dirt, corrosion, etc. When comes to replacing caps, always buy new. In this case, I'd replace them any way.

 

[JimDawson]

I think I'll buy another 3 phase motor and replace. now the VFD, is that a separate unit that I buy or does the motor come with it installed? I'm new to all this. can I just buy any compatible 3phase motor now and install VFD later?

As Bob says not just any motor will fit your Bridgeport, they are a special frame size. Again I recommend taking the motor to a motor shop and get it checked out. The VFD is a separate unit, but it will allow a single phase input and output true 3 phase, so no lost HP. And you get variable speed as a bonus. Cost of a VFD for that motor would be in the $150 range.

 

[John Hasler]

The start and, if it has one, run capacitors will age even when not used. Ten years is a long time for those buggers. Take apart the motor and your converter and look at the caps. If the caps looks swelled and/or cracked, replace. While you are about it, check for dirt, corrosion, etc. When comes to replacing caps, always buy new. In this case, I'd replace them any way.

Electrolytic start caps age. Run caps are usually sealed oil filled types that last forever if not damaged.

 

[Milehimachine]

I ran into this issue when working in my dad's shop, forgot to plug in the phase converter motor and tried running his 3 phase Logan lathe was not a good experience. Because there wasnt that third phase coming to the motor it destroyed the motor. I would do what others here have said get the motor checked and add a VFD then you will have no worries. Automation direct has great deals on VFD's all the time.

 

[CluelessNewB]

10 years of no running may have allowed critters to move in. Things like mice, wasps, bees...

 

[Bob Korves]

Many motors can be wired for alternate voltages. Your motor may be wired to a voltage different than what your static converter is supplying.