Teco VFD on Gorton mill help

[Liljoebrshooter]

I just brought home a Gorton 1-22 mill and bought a TecoL510 VFD to power it. I have been reading about hooking these up quite a bit, and the more I read the more confused I become.
I tried to power it up by just hooking the output from the vfd to the 3 wires from the electrical box that contains all the relays and contactors. Nothing worked, so I just hooked th vfd directly to the leads from the motor. It fired right up. The issue I am facing is powering the feed motor on the table.
My question is, can I, or should I eliminate the contactors after the vfd and run directly to the motor?
Question 2. How can I power the transformer for the power feed motor if I do eliminate the other stuff?
I will try to attach a picture of it.
Thanks for any help you can give me.
Joe Hynes

 

[Ulma Doctor]

Hi Joe,
unfortunately VFD's do not work with magnetic contactors or transformers on their output.
a VFD's main output is designed simply for running a motor only
if your power feed motor is not the same voltage as the main motor, you will not be able to run them from the same VFD
if the power feed motor IS the same voltage as the spindle, you could use the same VFD, with a drawback
both motors will use the same output of the VFD and both will be confined to the same frequency
the other option off the top of my head is to Run a VFD for the spindle, then also supply single phase to the transformer and control circuit for the power feed to restore normal OEM operation in that circuit

 

[markba633csi]

Joe: Ulma is correct you will be connecting the VFD directly to the motor bypassing the contactors. The power feed transformer will be powered from single phase 120 volt or 240 volt- you need to check what voltage(s) can be used with it, should be marked on the transformer itself but sometimes you need the actual diagrams and data for the machine. Do you have any manuals or schematics?
Mark S.
ps do I see some crispy components on the power feed board? A close up pic would be helpful
looks like a blown? fuse on the floor of the power feed box- an ominous sign but it could just be a spare

 

[Eddyde]

Since you cannot practically run the spindle and feed at the same speed and direction at the same time, you should probably just get a 2nd VFD to power the feed motor. You cannot have any switches or contractors between the VFD and the motor, All control wiring must go to the VFD.

 

[cathead]

Hi Joe and welcome to the Hobby Machinist forum.

The easy way to run your machine would be to use a rotary phase converter. My 9J Gorton has basically the
same set up and everything works using the RPC. You would not have to rewire anything that way. I would guess
that your feed motor is 220V 3 phase as well. It's very easy to make an RPC using a 3 phase motor so worth the
consideration, inexpensive as well.

 

[Liljoebrshooter]

Here is the tag from the transformer. I made the connections to change the input voltage to 220 when I was making all the others connections. I pulled the fuse out so if something was incorrect it wouldn't fry everything.
I was reading last night about not being able to use any contactors in the circuit with a vfd. This will let me eliminate most of the old stuff in that panel, so that actually sounds good to me.
Now I need to figure out how to hook up the circuit to the feed motor transformer. I was hoping I could wire a relay into the power switch circuit so it would be on one switch.
Thank you for the help guys.
Joe Hynes

 

[Liljoebrshooter]

So I have been doing some more reading and I think the terminals RA and RB are for switching a relay? So all I should need to get is a relay for 220v and wire it to the on-off?
Am I heading in the right direction?
I know this can be done, I just need someone smarter than me to show me how to do it correctly.

 

[Eddyde]

Not sure what you are trying to achieve; send power to the feed motor only when the spindle VFD is powered up?
Also, I see the feed motor is DC, so a second VFD is not an option.
Might want to follow Catheads suggestion and go the RPC route.

 

[Liljoebrshooter]

Yes I would like to have the feed motor transformer powered only when the main motor is running. I could just run a separate switched feed to it but I'm worried that I will forget to turn it off and end up burning up the transformer.

 

[cathead]

The plot thickens....

You could run the main motor with the VFD and take some power off the transformer and make a simple bridge rectifier to power
DC feed motor, thats assuming the transformer is powered up all the time. What does it say on the transformer? Is it a single phase
transformer and what is it used for in it's present state? Apparently the feed motor has been changed out or something. You might as
well take advantage of the VFD if you can. Another option would be to build up a simple power supply for the feed motor and run it on 120V AC single phase.