VFD for Machine Tool

entropy · #1 03-15-2018, 07:48 PM

I know it can be done, but not how...
That and there are about a bijillion+1 choices... sizes, ratings, colors and

Is there anyone here that can help me build/apply a VFD set up, for two of my mills?

TIA

E

alwaysFlOoReD · #2 03-15-2018, 11:24 PM

https://www.garagejournal.com/forum/...7120&showall=1

stock93 · #3 03-16-2018, 08:38 AM

E,
What exactly are you trying to figure out? I've done this multiple times myself with great success. I have three pieces of 3 phase equipment running on VFD's plus a 30 hp RPC in my shop. Post some specifics of what you have and I'll try to guide you in the right direction.

John

Graham08 · #4 03-16-2018, 09:29 AM

I haven't had to go down this path yet, but I've done some reading. There is a "Phase Converters and VFD's" forum on Practical Machinist that has a lot of information.

entropy · #5 03-16-2018, 02:30 PM

Quote:

Originally Posted by stock93

E,
What exactly are you trying to figure out? I've done this multiple times myself with great success. I have three pieces of 3 phase equipment running on VFD's plus a 30 hp RPC in my shop. Post some specifics of what you have and I'll try to guide you in the right direction.

John

I have two Vertical Knee mills that have been in storage for far to long.
One is a 3HP and the other is a 2HP both are Induction Motors.
I can get 3PH and the last quote by the local power COOP was $25k Minimum.
So I need to do a 'Phaze Conversion up from 220-SP to 220-3P.
I do not want to listen to a RPC so Rotary Conversion is, all but, ruled out.
That leaves a Static converter, or a VFD.
It appears that going with the VFD has some advantages and right about there
the Internet suddenly has a cubic metric ton of often contradictory information
and most of it appears to be several years old...
While I don't need all of these functions but this is what I would like:
THIS
except I think the price is a bit high, as in WAY!! However, I only think it is high...

E

entropy · #6 03-16-2018, 02:31 PM

Quote:

Originally Posted by Graham08

I haven't had to go down this path yet, but I've done some reading. There is a "Phase Converters and VFD's" forum on Practical Machinist that has a lot of information.

Information overload, lots to read!

E

entropy · #7 03-16-2018, 02:32 PM

Quote:

Originally Posted by alwaysFlOoReD

https://www.garagejournal.com/forum/...7120&showall=1

Thank You!

bullnerd · #8 03-17-2018, 01:37 PM

I ran my proto trak knee mill on one of the cheap phase-o-matic converters for years without trouble. Everyone will say you cant get full HP out of them, but I worked 25 yrs in various machine shops and never noticed a difference in power between the ones in industrial shops and the one in my garage.

If you still want to go VFD, this guy knows his shit. As long as its still the same guy! LOL!

Site is easy to select what you want also, but calling is even easier.

http://www.google.com/url?sa=t&rct=j...01DCqak07v5jiV

entropy · #9 03-17-2018, 03:06 PM

Quote:

Originally Posted by bullnerd

I ran my proto trak knee mill on one of the cheap phase-o-matic converters for years without trouble. Everyone will say you cant get full HP out of them, but I worked 25 yrs in various machine shops and never noticed a difference in power between the ones in industrial shops and the one in my garage.

Agreed, but the VFD would also change the one mill from a step drive to a variable drive...
That would be nice.
Of course I could just sell it and put that $$$ towards the Lathe I want...

E

R.DesJardin · #10 03-17-2018, 06:29 PM

Quote:

Originally Posted by entropy

Agreed, but the VFD would also change the one mill from a step drive to a variable drive...
That would be nice.
Of course I could just sell it and put that $$$ towards the Lathe I want...

E

You lose hp with a VFD as you change the hz up or down from the standard 50/60. The new rotary's aren't loud like the old screaming ones.

entropy · #11 03-17-2018, 07:00 PM

Quote:

Originally Posted by R.DesJardin

You lose hp with a VFD as you change the hz up or down from the standard 50/60. The new rotary's aren't loud like the old screaming ones.

This is what I find frustrating! I've heard both: You lose power; You don't lose power with the VFD. . . but (and I think it is agreed) you always lose power to a Static Converter. and the rotary has its own set of quirks...
This research is frustrating... like buying Snake Oil

E

stock93 · #12 03-18-2018, 10:03 AM

A RPC is nice for big loads where you don't need speed variation. I have a two full sized VMC's and a lathe with a 7.5 hp motor so it's worth having for that. I don't listen to my rpc at all as it's outside. I wired in a sub panel inside the shop and ran wiring to each machine. With the rpc humming away outside its just like having 3 phase from the pole as far as operation. I wouldn't go through the trouble for a single 3 hp mill. On my mill I mainly wanted the vfd for being able to turn my step pulley J head into a variable speed machine. It works excellent for this. It's awesome for power tapping as you can slow it way down and just feed the tap into the material as deep as you want then retract it. I think mine will run at 20 rpm in low gear as low as I have the bottom of the Hz range set.

I have been running two of these drives for years without issue. They will work to do what you are wanting to do. They were around $300 ea when I bought them. They come with a decent book for installation and setting them up.
https://www.tecowestinghouse.com/products/Drives/EV.htm

With a vector drive you aren't supposed to loose much hp as you vary the frequency. Their is no perceived power difference in my mill if you're running 30Hz, 60Hz, or 90Hz.

entropy · #13 03-18-2018, 04:20 PM

Quote:

Originally Posted by stock93

SNIP<
I have been running two of these drives for years without issue. They will work to do what you are wanting to do. They were around $300 ea when I bought them. They come with a decent book for installation and setting them up.
https://www.tecowestinghouse.com/products/Drives/EV.htm

That drive is obsolete and this drive is the replacement:
http://dealerselectric.com/L510-203-H1-N.asp
Price is right

E

bullnerd · #14 03-18-2018, 08:12 PM

Quote:

Originally Posted by entropy

Agreed, but the VFD would also change the one mill from a step drive to a variable drive...
That would be nice.
Of course I could just sell it and put that $$$ towards the Lathe I want...

E

Yeah, I didn't think about the step pulley deal.

I did some pretty decent hogging on my p-trak, never had an issue with the phase-o-matic.

entropy · #15 03-19-2018, 11:45 AM

Quote:

Originally Posted by bullnerd

Yeah, I didn't think about the step pulley deal.

I did some pretty decent hogging on my p-trak, never had an issue with the phase-o-matic.

The Phase-o-Matic is actually a little higher $$$ then a VFD...

bullnerd · #16 03-19-2018, 07:27 PM

Quote:

Originally Posted by entropy

The Phase-o-Matic is actually a little higher $$$ then a VFD...

Muhahaha! I didn't know that. Just leave me out of this conversation.

But they are super easy to hook up!

stock93 · #17 03-20-2018, 07:57 AM

So is a VFD. It's wall power wires in, three phase to the motor out. The only extras are for the control switch.

I started off running my lathe off a Phase-o-matic. I noticed my surface finishes kinda sucked. Swapped to a rpc and the problem went away.

entropy · #18 03-20-2018, 01:33 PM

Quote:

Originally Posted by stock93

So is a VFD. It's wall power wires in, three phase to the motor out. The only extras are for the control switch.

I started off running my lathe off a Phase-o-matic. I noticed my surface finishes kinda sucked. Swapped to a rpc and the problem went away.

This^
Now I need to narrow down the features on the VFD.
Hope to order by the end of the week.

Thanks to all again

E

TheBandit · #19 03-20-2018, 01:44 PM

Cool to see the level of input on this thread. I wish I had something to contribute but I forgot what little I knew about VFDs. I used them in process automation to run pumps and conveyor systems with PLCs.

Hope to see photos of the project.

CarterKraft · #20 03-23-2018, 10:45 AM

I used the cheapest 3hp VFD off evilbay I could find for my old Buffalo drill press.

I couldn't be happier and after not doing it 4 years sooner I was pissed at myself for putting it off.

I still want to hook up the drill presses start/stop buttons add a RPM dial and a foot switch but so far running it all off the VFD itself has been fine.