Installing first VDF for drill press - questions

Thread Starter

ryanjg117

Joined Nov 3, 2017
19
Howdy. Installed an air compressor auto-drain with help from this forum last time, hoping for similar success the second time around!

I purchased secondhand a beautiful Powermatic 1150A drill press, with a 3-phase Baldor motor. Sadly, I only have single phase 220v in the shop. So, I went on AutomationDirect and purchased a GS1-21P0 micro-drive to convert that single-phase signal to three-phase for the Baldor 1hp motor. Setup looks to be rather straightforward so long as I can navigate the menu structure.

A couple questions about my application:

1. This Powermatic drill press already has adjustable speed via a control switch at the top of the unit. Is there a benefit to using the speed adjustment on the VFD? The Baldor motor nameplate says 1,725 RPM and I believe the speed control at the top goes from 450 to 4800 RPM, which pretty well covers all woodworking use cases although I suppose it would be nice to go even slower than 450 RPM for occasional metal work.

2. Related to the previous question, is there a chance I could screw up the variable speed components of the drill press by fiddling with the motor speed at the VFD? The only warning I read in the manual was not to run the motor at greater than its 1,725 RPM.

3. The manual lists some application examples as categorizes them as "constant torque" and "variable torque" applications. I would imagine a drill press is going to be constant torque, correct? There is also a setting to require high torque on startup - would that be necessary here?

4. I purchased a NEMA enclosure for it as it's not really intended to be very dust resistant. This enclosure has standard electrical knockouts, but I was thinking about installing a vent at the bottom and a small computer fan on the top, just to get hot air out of the enclosure. I'm wondering if I can run this small case fan off the outputs on the VFD itself. There are the following outputs on the unit: R1 (relay output common), R10 (relay output normally open), and +10VDC output. Might any of these work for a standard case fan?
 

jpanhalt

Joined Jan 18, 2008
9,725
I suspect that variable speed drive on the Powermatic is a variable pitch pulley. I have converted an older Jet 14" drill press (made in Japan) with step pulleys to 3-phase with VFD. Left the old step pulley intact. No problem. At the slowest mechanical speed and w/ VFD, it turns extremely slowly (winding coils? sanding? countersinking steel?). At a medium mechanical speed and w/ VFD I get a speed range for almost anything.

I would leave the mechanical control in place.
 

be80be

Joined Jul 5, 2008
2,047
+10V Internal power supply (10 mA @ 10 VDC) don't run a fan off that you'll burn out the supply
Get a wall wart for your fan none of the output are for sourcing power
 
You should be able to set the VFD to use the 450 to 4800 RPM units/ and keep the speed control at max.

Lower RPM should also be possible either directly via the VFD or through the pulley system.

The benefit of the VFD is constant torque.

More torque on start-up? I'd say no. A drill should start up unloaded anyway.
 

Thread Starter

ryanjg117

Joined Nov 3, 2017
19
One more Q - the drill press came with a Telemechanique LE1 D123 (the black box on the rear). I believe this is a starter for the 3-phase motor. Is it still necessary with the VFD in place?
 

MaxHeadRoom

Joined Jul 18, 2013
20,898
Normally by code you should have an input disconnect operated by a E-Stop PB.
The normal stop/start will input to the VFD PLC inputs.
Max.
 

jpanhalt

Joined Jan 18, 2008
9,725
Here's the manual for that machine: https://www.sterlingmachinery.com/media/brochures1/file/Powermatic-Model-1150-A-15-(381-mm)-Drill-Press.pdf

The VS head is a variable pitch pulley. I would definitely keep it. The original was 3-phase, and there seems to have been three versions, a simple switch , magnetic starter, and LV magnetic starter. What you purchased looks more like a shop installation, not factory.

My VFD's have soft start and are operated with simple push button mechanical switch. I don't see any value in making it more complicated unless required by some code. You might find a push button switch to fit that head casing. Then hang the VFD off the back -- probably on that plate that looks shop made.
 

jpanhalt

Joined Jan 18, 2008
9,725
To start or stop your VFD (I am assuming there is a typo in your title, i.e., VDF = VFD) that will work, but is probably overkill. HOWEVER, I do not like toggle switches on machinery. Push on, push off is my preferred method. Often the red push off stands out further and is sometimes even much bigger. Here's just one example:

upload_2019-7-22_15-2-14.png

To repeat, I do not think your VFD will require the Telemechanique starter. You "START" the VFD and then it does its thing. To be sure, post a link to the installation directions for your VFD,
 

jpanhalt

Joined Jan 18, 2008
9,725
I took only a quick look at the manual. You can have both a remote potentiometer for speed control and Run/Stop can be external terminals (see: Chapter 2-9 for instance). That is exactly how my drill press is set up with a different brand VFD (KB Drives). Run/Stop are the standard push buttons and are wired to terminals on the VFD. In the picture below, the standard buttons are shown. The VFD is the red box below the motor. The little lever at 2 o'clock from the spring return for the spindle is a drag lock I installed to hold the spindle in a partially down position.

upload_2019-7-22_15-48-3.png

This is the speed control (black knob above the depth handles). I had to drill a small hole in the head casting for it. Since the Run/Stop was on the left, the only space left was on the right side. If I had had front-mounted buttons, the speed control would have been on the left side so as not to interfere with drilling. It is a very minor inconvenience where it is. One thing you don't want to do is reach over the work piece or behind the machine to do anything critical. I suspect that's obvious, but worth repeating.

upload_2019-7-22_15-51-2.png

You have a nice machine.

John
 

Thread Starter

ryanjg117

Joined Nov 3, 2017
19
John, thanks for digging into the manual. For wiring the on/off switch directly to the drive, what input should I be using?
 
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