Any 3 Phase Motor Gurus Here?

[Kenwc]

I have a really nice old 1/2 HP Atlas 3 Phase motor on my Atlas model 73 drill press. I'm using a Teco FM50 VFD.

Even at the highest speed I can grab the drill chuck by hand and stop the rotation. I don't know if I'm dealing with a "weak" motor or if there is some setting on the VFD to check.

Other than this problem the motor is smooth and quiet and runs forever like new.

Anyone have any ideas?

Thanks

 

[ndnchf]

I can't answer your question, but I can tell you I have a 220v three phase, 3/4hp baldor motor on my WT900 DP. It runs off 115v through a TECO FM50. It's has plenty of power at any speed. The belt might slip if it jams, but the motor has never stalled. Something sounds wrong with yours, but I don't know what.

 

[disneyjoe7]

Run Cap?

 

[Techie1961]

Run Cap?

It's 3P so it won't have caps.

Are you sure that the parameters are all set correctly? Who did the programming on it?

 

[Kenwc]

Someone else set the parameters...I think I'll call the Teco techs tomorrow and ask them about this...I can think of no reason why this motor would do this other than the VFD not being set correctly.

I have another 3 phase motor driven by a Teco that would twist my arm off if I tried to grab the chuck

 

[marinusdees]

The speed of the motor should be constant since it is 100% dependent on the frequency which is constant, being delivered by the freq drive. If the motor is slowing, it must be due to overload, and this will result in motor failure and/or overheating, in SHORT order. Check to see that frequency stays constant, although I have not seen a freq drive which can be programmed to change its own frequency without user input.

 

[larry_g]

http://www.tecowestinghouse.ca/wp-content/uploads/mm_FM50_Manual_04_05.pdf

The above is the manual for your unit, some things to check;

1. Is the drive rated HP matched to you motor? page 11

2. Check your F 13 and F 18 settings. pg 40-44

For the rating check the manual for the drive number that matches your motor. Then scroll down the manual and see what f13 and f18 does, and it they are set correctly. You probably should scroll through all the settings and WRITE them down before changing anything. Do this before contacting TECO so at least you can understand them and have a chance at an intelligent conversation.

lg
no neat sig line

 

[kkroger]

Sounds like you don't have the Legs Wired right...
At the Motor...

 

[larry_g]

Sounds like you don't have the Legs Wired right...
At the Motor...

Good call, Is this a multi-voltage motor? How many wires are their available to play with? Can you picture the motor nameplate?

lg
no neat sig line

 

[Dagny]

wired 240 running on 120

 

[Kenwc]

wired 240 running on 120

I've heard this twice...and I've not checked this...I will now...

Thanks

 

[454ragtop]

wired 240 running on 120

Never heard of a 3 phase motor that was able to be wired to run on 120 volt, at least not without a 120 volt input VFD.

 

[Kenwc]

I checked the motor and it's a 220V 3 phase so it should work fine on the Teco FM50 I'm using. I suppose the 4th leg could be wired wrong inside the motor junction box. I'll have to open and see. There are no wiring plates on the motor.

 

[marinusdees]

Three phase motors will run on single phase, it's called "single phasing". There must be three phase present to start rotation, but after it is started, one leg can drop out, either inside the motor a winding opens, maybe centrifugal force? or the freq drive has an internal component dropping out. "Single phasing" will produce the symptoms you describe, i.e., running, but making no power. Check your point to point voltage under running conditions. Just sayin'.

 

[Kenwc]

Good information also....thanks

Three phase motors will run on single phase, it's called "single phasing". There must be three phase present to start rotation, but after it is started, one leg can drop out, either inside the motor a winding opens, maybe centrifugal force? or the freq drive has an internal component dropping out. "Single phasing" will produce the symptoms you describe, i.e., running, but making no power. Check your point to point voltage under running conditions. Just sayin'.

 

[EricP]

I checked the motor and it's a 220V 3 phase so it should work fine on the Teco FM50 I'm using. I suppose the 4th leg could be wired wrong inside the motor junction box. I'll have to open and see. There are no wiring plates on the motor.

Is it a 220V only motor? Or can it be wired for 220 or 440 which is very common on 3 phase motors? To me it sounds like it is wired for 440 but being fed 220. Is the motor wiring diagram readable? It might have two diagrams, one "Low Voltage", and one 'High Voltage". You want it wired for "Low Voltage" for your particular VFD.

 

[Kenwc]

There's no visible wiring plate. What I need to do is see if it's either inside he access plate on the end bell or perhaps under paint on the outside of same plate.

Thanks

Is it a 220V only motor? Or can it be wired for 220 or 440 which is very common on 3 phase motors? To me it sounds like it is wired for 440 but being fed 220. Is the motor wiring diagram readable? It might have two diagrams, one "Low Voltage", and one 'High Voltage". You want it wired for "Low Voltage" for your particular VFD.

 

[Stuart in MN]

Dual voltage motors will have that stamped on the motor plate. Since this one says only 220 I doubt it can be wired as 440.

My guess is there's some parameter in the VFD that's not set up correctly.

 

[EricP]

Dual voltage motors will have that stamped on the motor plate. Since this one says only 220 I doubt it can be wired as 440.

My guess is there's some parameter in the VFD that's not set up correctly.

I typed my post from work where the picture was stripped by the network Nazis. Couldn't even tell there was a picture above my post. Now that I can see I agree, that doesn't look like a dual voltage motor.