VFD to 2 motors

This forum is dedicated to those hobbyists with the 3-in-1 metalworking machines. Mill-Drill-Lathes. Tips, techniques, modification and use of these machines is topical.

Moderator: Harold_V

User avatar
liveaboard
Posts: 1961
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: VFD to 2 motors

Post by liveaboard »

I think you're not looking in the right places; any electrical supply should have such switches.
I used a 4 pole rotary switch for that job [1 VFD for my drill and my lathe]; I used the fourth pole to switch the forward/back control to the appropriate switch. Speed control stays near the VFD on my installation.
VFD instalation.jpg
User avatar
Steggy
Posts: 1973
Joined: Tue Jun 28, 2011 9:19 pm
Location: JB Pritzker’s Hellhole
Contact:

Re: VFD to 2 motors

Post by Steggy »

John Hasler wrote: Thu Dec 31, 2020 4:45 pmShields should not be grounded at both ends. Between buildings use RS422.
You're preaching to the choir. :D The problem is signal ground is usually bonded to the equipment chassis. Even if the shield was only terminated at one end the current flow from GPPI could pass through the signal ground (pin 7 of a DB-25 in a TIA-232 circuit) and cause trouble.

Back then, TIA-232 to TIA-422 converters were costly, and not all that reliable. Ditto for TGIA-232 to TIA-485. Since all peripherals were TIA-232, choices were very limited. As I said, if we needed to connect to a different building we'd set up fiber. If the distance required it, we'd use a short-haul modem.
———————————————————————————————————————————————————————
Music isn’t at all difficult.  All you gotta do is play the right notes at the right time!  :D
SteveM
Posts: 7763
Joined: Mon Jun 27, 2005 6:18 pm
Location: Wisconsin

Re: VFD to 2 motors

Post by SteveM »

How about having a single 3-phase outlet on the wall by the VFD and have the power cords for both machines hanging on the wall by the outlet?

You can't plug both in at the same time - it's not only foolproof, but idiot proof.

I'll bet that will be a lot cheaper than any other solution, and believe me, I know cheap - it's my middle name.

Steve
toddalin
Posts: 284
Joined: Tue Nov 13, 2012 1:10 pm
Location: Orange County, CA
Contact:

Re: VFD to 2 motors

Post by toddalin »

Should only need two contactors.

Go on ebay and look for three pole contactors. Chinese pieces are <$10 each. American quality may cost a few dollars more. I can't imagine that you would need to switch more than 20 amps, but you can easily find them that can handle over twice this current.

These are just examples.

https://www.ebay.com/itm/CJX2-1201-Moto ... Sw9bBZlrTz

https://www.ebay.com/itm/NEW-Honeywell- ... SwALdczGUn
VelocityDuck
Posts: 118
Joined: Mon Dec 07, 2020 6:14 am
Location: Panama City, FL

Re: VFD to 2 motors

Post by VelocityDuck »

Was looking for something elegant. 2 contactors, wall warts and a switch certainly isn't that.

I guess the VFD controller going to a plug and the motors going to a pair of outlets will be the easiest way to go.

Thanks for the input guys!
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: VFD to 2 motors

Post by John Hasler »

> I guess the VFD controller going to a plug...

Giving you bare prongs that could have 240VAC on them. Don't ever do that.
User avatar
liveaboard
Posts: 1961
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: VFD to 2 motors

Post by liveaboard »

I think he means a plug outlet.
Torch
Posts: 1684
Joined: Wed Mar 17, 2010 7:58 am
Location: Muskoka

Re: VFD to 2 motors

Post by Torch »

Funny, my machine came with one controller (single phase DC, but still...) and a switch. I got rid of the switch and added a second so I could run both motors at the same time. I use the lathe motor as a powerfeed when milling.
VelocityDuck
Posts: 118
Joined: Mon Dec 07, 2020 6:14 am
Location: Panama City, FL

Re: VFD to 2 motors

Post by VelocityDuck »

Yeah, but the controllers are about $250 each. I already feel like I'm putting a $100 saddle on a $25 horse by doing this. Granted the difference is $1,000 instead of $750, but that extra $250 could buy some additional tooling.
User avatar
liveaboard
Posts: 1961
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: VFD to 2 motors

Post by liveaboard »

I got mine on ebay for $50.
Sometimes you can get a bargain if you wait.
VelocityDuck
Posts: 118
Joined: Mon Dec 07, 2020 6:14 am
Location: Panama City, FL

Re: VFD to 2 motors

Post by VelocityDuck »

That is certainly true. Except that this is just a bit outside my wheelhouse. The Clough42 guy had the exact same motor as I have so I know the motor and VFD he chose will work for me. I've looked for the Teco L510-101-H1 on eBay but after shipping it's not much cheaper than new. If I try a different make/model of VFD and discover that there's some minor difference that I didn't know about then I'm in uncharted territory trying to figure out how to make it work. This might be a no-brainer for someone who's done it before.
toddalin
Posts: 284
Joined: Tue Nov 13, 2012 1:10 pm
Location: Orange County, CA
Contact:

Re: VFD to 2 motors

Post by toddalin »

I got a TECO JNEV-101-H1 brand new when I got my machine. But it doesn't have the capacity for my machine and has been on the shelf ever since. Is this something you could use? (1HP/750 Watt)

Just like this one:
https://dealerselectric.com/JNEV-101-H1.asp
Image
Post Reply