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John Sincerbeaux
08-29-2019, 12:44 PM
I am making a relatively small spray booth which will incorporate a 3 phase 12” tubeaxial fan. I want the fan to be variable speed so I can dial in the CFM of the booth.
The fan will have a 3/4 hp motor belt drive motor so i think I’ll only need a 1hp VFD.
Any recommendations on an industrial quality VFD? The VFD will be mounted on the shop-side of the booth so will I need a NEMA 4 rating which I guess means a more dust proof enclosure?
Do all VFD’s make a piercing whining sound? Steve Rowe has a video on his Extreme Woodworker channel regarding 3 phase options. He shows a VFD powering a 3 phase disc sander. But the noise it makes would drive me crazy.

Last question? I have 3 phase power in my shop. Is there such thing as a 3 phase to 3 phase variable speed controller?

Thanks

Dave Cav
08-29-2019, 1:11 PM
To answer your last question first, yes, VFDs were originally developed years ago for three phase service speed control for fans, pumps and industrial processes. The use of VFDs for phase conversion is a relatively recent development.

I have six or seven TECO FM50 VFDs in my shop and they are dead silent, but they are not NEMA 4 rated. I do have an Automation Direct VFD on a drill press in the garage which has a fan which runs continuously, which I find annoying, but it's a fan noise, not a piercing whining sound. I just turn it off when I'm not using it and when I'm running the drill press I can't hear the VFD fan.

If you go to the Factorymation or the Automation Direct web pages you will probably find what you are looking for; if not they both have good technical assistance a phone call away. They aren't as cheap as buying a no-name VFD off Ebay, but you're paying for their expertise and technical assistance.

Jim Peck
08-29-2019, 1:12 PM
I am making a relatively small spray booth which will incorporate a 3 phase 12” tubeaxial fan. I want the fan to be variable speed so I can dial in the CFM of the booth.
The fan will have a 3/4 hp motor belt drive motor so i think I’ll only need a 1hp VFD.
Any recommendations on an industrial quality VFD? The VFD will be mounted on the shop-side of the booth so will I need a NEMA 4 rating which I guess means a more dust proof enclosure?
Do all VFD’s make a piercing whining sound? Steve Rowe has a video on his Extreme Woodworker channel regarding 3 phase options. He shows a VFD powering a 3 phase disc sander. But the noise it makes would drive me crazy.

Last question? I have 3 phase power in my shop. Is there such thing as a 3 phase to 3 phase variable speed controller?

Thanks

I'm the last thing from a VFD expert, but have been doing a lot of reading lately on the topic. In terms of the whining sound, my understanding is that you should be able to adjust the parameters to essentially eliminate it. And, yes, there are 3 ph input/3 ph output VFDs.

I don't have the depth of knowledge to recommend a specific drive. But I can recommend a company called Wolf Automation as both a place to purchase and a resource. For the drives I've been looking at, their price is competitive and they have first-rate customer service. I've called a couple times to discuss what I'm looking for and their tech support guys have been very helpful--and this is before I've bought anything. They don't sell no-name Chinese equipment, so you'll pay a little more than you would on Ebay probably, but in addition to a better product you'll have a seller in the US that will help you get the thing up and running. Well worth it in my book. I plan to purchase from them. All that to say, I suggest contacting them and talking through your intended application. They'll point you in the right direction. (No, I'm not a shill. And there are probably other companies out there with similarly good customer service. I'm just speaking from my limited experience.)

Dan Friedrichs
08-29-2019, 1:14 PM
I am making a relatively small spray booth which will incorporate a 3 phase 12” tubeaxial fan. I want the fan to be variable speed so I can dial in the CFM of the booth.

Have you considered just using a mechanical damper to limit the airflow? Would be much easier/cheaper.



Any recommendations on an industrial quality VFD? The VFD will be mounted on the shop-side of the booth so will I need a NEMA 4 rating which I guess means a more dust proof enclosure?

I can't imagine you'll find a 1HP VFD that you'd be disappointed with. I'd just pick a cheap one on ebay or one of these:
https://www.factorymation.com/TD200-2001-1PH

You may need to supply your own enclosure, but if you don't want to, see the ones mentioned in this thread:
https://sawmillcreek.org/showthread.php?276071-KBAC-27D-and-29D-VFDs


Do all VFD’s make a piercing whining sound? Steve Rowe has a video on his Extreme Woodworker channel regarding 3 phase options. He shows a VFD powering a 3 phase disc sander. But the noise it makes would drive me crazy.

Because the VFD is generating electric currents that may be in the audible range (which is unavoidable, if you want to turn the motor at those speeds), you may hear some squeal at some speeds. Newer VFDs often include ways to inject some disturbances to try to make those less annoying.



Last question? I have 3 phase power in my shop. Is there such thing as a 3 phase to 3 phase variable speed controller?

Thanks

Yep, a VFD :)

(VFDs are predominately used in industrial applications to control 3ph motors and are hooked to 3ph supply. It's a small set of applications where people want to turn 3ph motors but only have 1ph supply available. Any VFD you buy is probably "natively" designed for a 3ph input, but may also be operable off a 1ph input for those hobbyiest-type users)

Bill Dufour
08-29-2019, 1:59 PM
The VFD should not make noise beyond the fan. The motor may whine until you adjust the carrier frequency.
Bill D

John Sincerbeaux
08-29-2019, 2:53 PM
Great info guys. Thank you so much!

Darcy Warner
08-29-2019, 8:23 PM
Wolfe automation is great, the Fuji drives are great.

Factorymation is a place I no longer buy anything from.

Steve H Graham
08-29-2019, 8:26 PM
I have several VFD's. When a VFD is not adjusted correctly, it may cause the motor to make an obnoxious whistling sound. I'm sorry to say I can't recall the exact reason, but you will find it in your VFD manual. You simply adjust the VFD to minimize or eliminate the noise.

The down side is that you will have to read the manual, and they are not very good.

Doug Garson
08-29-2019, 8:40 PM
Another source of VFDs is Jack Foresberg who is a member on this forum.

Jon Nuckles
08-30-2019, 11:42 AM
Wolfe automation is great, the Fuji drives are great.

Factorymation is a place I no longer buy anything from.

I bought a Fuji VFD from Wolf Automation and have been very happy with it. The Fuji manuals are likely better than what you'd get with a VFD from eBay, which I have read are pretty bad. Wolf's technical service reps will spend time with you on the phone if you need help setting it up. My VFD makes no noise that I can hear, and it's on a drill press so there is not much accompanying noise to drown it out. My lathe uses a VFD, which came with it, and also does not whine.

John Lifer
08-30-2019, 8:39 PM
I have three made by Allen Bradley that I bought used from EBay over the years. All of them have a fan that comes on only when necessary. And the one that I use the most is powering my 1H.P. delta lathe. I have a three position switch that is Reverse off and forward,and a potentiometer that I can vary the speed. Easy and were cheap.

CPeter James
09-01-2019, 9:38 AM
I have 10 or 12 Automation Direct VFD. All are GS2 series. They do not make any noise that I can hear except the fan when the machine is actually running and that is not that loud. All have remote controls that you can build for less than $20, a three way switch and a 5K potentiometer. Support has been good, but the manual is so good, that about the only question I have had was "is it really this easy to build the remote?". Up to 1hp you can have 120V in and 230V 3 phase out. The programming is easy and gives you lots of options. If you buy used, you can reset to factory defaults with a couple of key punches.
Peter

Joe Calhoon
09-01-2019, 10:32 AM
John,
i have used a VFD on a 5 hp 3 phase spray booth for many years. It’s a nice application, when we were using solvent base you could turn the fan down low for a few hrs while the finish was off gassing. Keeping most of the heat in in the cold months.
With water base you can shut it off after spraying but it’s still nice to control the speed. We usually run at about 30%.
Mine whines but not too noticeable with the fan noise. I could probably read the manual and figure it out..
I am on the second VFD with this. Maybe running very slow is hard on these.

John Sincerbeaux
09-01-2019, 6:04 PM
Thanks Joe
Going to call Wolf Automation this week and see what they recommend. The Fuji’s look good. I’ll prob go with a NEMA 4 enclosure unit.
Thanks again everyone.
There’s a lot to learn about spray booths!!!
Another rabbit hole:)