3PH motor wiring

[Pevehouse]

Thank you guys. I appreciate all the response. I was able to manage wiring in the VFD and the programming but it’s been a while. Now oil can say I have never had to rewire the internals of a motor but now I feel I can. Thanks again

 

[Pevehouse]

Usually static phase converters are rated for a range of horsepowers... like 1 - 3hp. VFD's are usually just rated at their max hp. Are you sure you have a VFD and not a static phase converter?

In your pictures it looks like lines 4, 5, and 6 are all tied together which would indicate low voltage (230v) on the face plate. According to the face plate if it was wired for high voltage (440v) three of the leads from the motor would not be wired together. For high voltage here would be 3 pairs of 2 leads from motor wired together and the 3 incoming legs would be wired directly to 3 single motor leads... this does not appear to be the case. It looks like it is wired for low voltage (203v) to me.

I would suggest you get someone familiar with wiring up 3 phase motors to give you a hand, or at least onsite guidance.

Yes sir, it’s a teco VFD. I looked the manual up and that’s what it said was 1-3 at 230v

 

[Pevehouse]

Have you checked this fit on your lathe? The frame size is a 184, so most likely larger than the 1hp motor. I have a Taiwanese 12x36, there are very few motors that will fit without significant modifications to the motor area.

It looks to be wired to low voltage. There is one bundle with three wires, that should be 4-5-6, and I can see two other bundles of two wires, those bundles would be 1-7, 2-8, and 3-9. Each of those bundles would be connected to your three leads from the VFD. You can see where they cut those wires.

I have not done a test fit but I have taken a few measurements. It’s gonna be tight but I think we are good

 

[mksj]

Make sure your VFD is rated at 3Hp and the output amps are sufficient for that size motor, that is a big increase in Hp for that size lathe. You may also use a smaller motor pulley and over speed the motor to something like 100Hz, will give you a wider speed range.

 

[G-ManBart]

I honestly can't see a 12" gear head lathe of that style being able to use more than 1hp. My 14" Logan is a far more massively built lathe which can take some seriously heavy cuts and it doesn't come close to slowing down a 2hp motor.

 

[Pevehouse]

I honestly can't see a 12" gear head lathe of that style being able to use more than 1hp. My 14" Logan is a far more massively built lathe which can take some seriously heavy cuts and it doesn't come close to slowing down a 2hp motor.

I understand what you’re saying but I have been having some issues out of the 1 hp that’s on it. When I switch it on through the vfd my motor sometimes runs backwards for a couple seconds very slowly and makes a hum. I know it’s not the VFD or wiring so it’s got to be in the motor. Also if I try to take a heavy cut it bogs on me. I would have been good with a two hp but this one kinda worked out.

 

[Pevehouse]

Make sure your VFD is rated at 3Hp and the output amps are sufficient for that size motor, that is a big increase in Hp for that size lathe. You may also use a smaller motor pulley and over speed the motor to something like 100Hz, will give you a wider speed range.

Yes sir, it’s rated at 3 hp. Now the pulley trick is something I did not know. That’s always an option. Thank you

 

[Pevehouse]

You should link this topic over at the Electrical issues sub forum.

Love the user name by the way

 

[Harry Knutz]

Love the user name by the way

I'm sure some people get a good chuckle from it!

 

[Pevehouse]

I'm sure some people get a good chuckle from it!

Well I did,lol