View Full Version : VFD Mounting for SB Lathe

12-27-2009, 07:24 PM
Recently purchased an Automation Direct GS2 VFD for my SB 9 inch lathe. Now that I have a couple days of freedom from the day job I would like to get the VFD setup. My question is how did you guys mount your VFD drives? Did you use a metal enclosure, mount it on a panel, or something else? Thanks.

12-27-2009, 07:43 PM
Personally I like to be able to access the VFD while operating the lathe but you do have to allow for coolant, chips, wires, etc..

The problem with enclosures is they cost money, otherwise they would be great.

One of my lathe VFDs is mounted on the wall directly behind the lathe gearbox. It is out of harm's way and needs no enclosure (by my standards) yet I can still reach it while operating the lathe.

Another lathe VFD, with no wall handy, is mounted on a piece of unistrut attached to the lathe's rear splash shield. It is quite exposed there so I made a 3 sided enclosure out of OSB -- it looks lame and wouldn't impress an inspector, but it does keep most of the flying stuff and discourages stray fingers from making contact.

Doc Nickel
12-27-2009, 08:35 PM
While I like the features of the VFD, I dislike the teeny membrane type keys on the controller. I'd rather have big clicky switches that I don't have to worry about getting oil, chips or dust on.

In a recent remotoring (and re-remotoring) of my Logan 10", I upgraded to 3Ph, and added a GS2 as well. The Logan has a cabinet base, with plenty of room in the drive side. I don't store anything in the cabinet (other than some rarely-used items like the metric gears) so I figured I'd mount the VFD in there and add some external controls.

So first, I made this bracket...


... From some scrap aluminum I had laying around. It clamps to a support in the cabinet, as I didn't want to drill & tap or weld to part of the structure. It mounts like so:


Not only does it mount the VFD, but also shields it somewhat from any gunk that may be flung off the drive system. (It's actually pretty clean, so it's mostly a "just in case" situation.) Plus, it faces the VFD forward for easier access to the controls and for programming.

Mounted and running (and with yet another motor) it looks like this:


The orange cable is just a temporary pigtail for an extension cord- I still need to run 20A 220V service to that end of the shop. The blue line is 8-strand Cat-5 ethernet cable that goes to an armored conduit running up the back of the cabinet to my external controls:


It's a plastic utility box from Home Despot which I milled to hold two arcade game buttons (since the VFD works with just millivolt signal inputs), a Radio Shack 10K pot and knob, and an SPST switch for reversing.

It all works quite well, and is a major improvement over the single-phase 1-1/2 HP it had previously. And I like this control setup so much, I'm strongly considering redoing the VFD controls on both the other lathe and the horizontal mill, and will probably make a fourth whenever I get around to putting the old mill-drill back together.


12-27-2009, 08:58 PM
Hey Doc, SPST for reversing?


Doc Nickel
12-27-2009, 09:12 PM
Hey Doc, SPST for reversing?

-Yep. It's just a signal to the electronics, not an actual physical connection to the motor.

As far as the VFD is concerned, no signal on that pair means "start normal rotation", and a positive signal (closed connection) means "start reverse rotation".

There's other options for wiring- as I recall, there's a way the GS2 can be set for two separate buttons; one forward start, and one reverse start, with a third "all stop" button. I preferred a standard start/stop with a separate reverse switch since I don't use rev much.