Recommendation? 1-Phase 110v Motors with VFD for 2x72 Grinder Frame

H

honingblades

Joined
Oct 4, 2018
Messages
72
Hello,

I'm looking at picking up a 2x72 grinder. I'm looking at sourcing my own motor and vfd but a bit confused.

For context. The two grinder frames I am looking at are:

- Northridge Mod-E
- Ameribrade 272

I am open to other suggestions for a new/completely entry-level knife maker as well...

I've watched a ton of youtube videos but people seem to say you need a 3-phase motor which requires 220v (I only have 110v) to use a vfd. I can't seem to find a 3-phase motor that's wired for 110v. Lots of comments in youtube videos as well where people say I need a 3-phase, yet I see on full grinder build websites where they list the motor and vfd as:

"Variable speed 2hp, kbac-27d vfd, wired for 110v"
"1.5 hp motor & kbac 27 d variable speed drive"
"110-120 volt 1 phase with 1.5 HP motor and Kbac 27d"
"You are correct the VFD will not work with a single phase motor. If you want speed control with a single phase motor on a belt grinder, you will need to use a pair of step pulleys."
"he is correct. No speed control on a single phase motor."
And the list goes on...

So yeah, a bit confused here.

Does this mean I wont be able to use the VFD to control speeds with a 1-phase motor? I understand I wont get more than 1.5HP on a 2HP motor with 110, but I think that will be fine until I get better/demand more from the machine.

I'm not a motor guy, but looking to save a bit of money by trying to find my own motor/vfd. I know someone that can wire it for me, but he doesn't know much about motors and vfds.

This is one I was looking at for example: - https://www.automationdirect.com/ad...eneral_purpose/general_purpose/mtr2-1p5-1ab36 (open to other suggestions as well)

To pair with a VFD - https://www.amazon.com/gp/product/B01AOCLIEU (also open to cheaper alternatives)

But honestly I have no idea.... :)

Much appreciated.
 
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Yep, what you've quoted is correct. The good news is that a VFD can take single phase power and convert it to variable frequency three-phase, even at higher voltage than your input power. You would use the VFD you linked with a 220-240V three-phase motor. The motor you linked would not work with a VFD.
 
You won't find a 110v 3 phase motor (at least not easily...), and a VFD will NOT work with a single phase motor (at least not easily...) heheh
As Nick said, the VFD does the work of converting your 110V input to 220V 3 phase power (or at least a simulated 3 phase). You'll be able to get up to 1.5hp with a 110 input on the KBAC-27d, or if you upgrade to 220V input in the future, you can run up to 2hp, you'll just have to set the jumpers accordingly.

Keep in mind that the VFD you linked to will not come with a power switch or a forward/reverse switch. This isn't a huge deal as you can just switch your power supply off to the VFD, or some guys just leave them on 24/7, though I don't particularly like that option. Don't forget about cable glands, cables, plug ends, etc...
 
honingblades said:
I've watched a ton of youtube videos but people seem to say you need a 3-phase motor which requires 220v (I only have 110v) to use a vfd. I can't seem to find a 3-phase motor that's wired for 110v. Lots of comments in youtube videos as well where people say I need a 3-phase, yet I see on full grinder build websites where they list the motor and vfd as:
Click to expand...
The simple explanation is: The 110v single phase from your wall outlet enters the VFD by one cable, and through the Wizardry of Electronic Circuit board is converted to 3 Phase power which exits the VFD by another cable connected to a 3Phase Motor 208/430v. Yes you need a 3 phase motor your confusion is by the voltage ratings 110/220v are common house current 208/430 are industrial/commercial current which allows Large industrial equipment to run more efficiently. The KBAC 27 referenced will convert either 110/220v (220 is more efficient and will yield full HP of a motor) to 3 Phase I have a couple of these units myself and consider them the best for a dirty work area because of the NEMA4 enclosure.
 
Just to clarify for those who get confused, voltages are stated in many ways.

For our simple purposes and as far as the VFD cares - 110/115/120 are all the same and 208/220/240 are all the same. Most people just say 120 and 240 in the USA, regardless of the actual power in their area.

When you see 120/240 or 220/440 that means a VFD can be configured to run at those two output values. Motors are similar with 120/240 being common. You can run the motor on 120 or 240 volts. You have to move some jumpers to select which one the motor is rated for. If that does not make perfect sense to you, get someone who understands wiring to hook things up.

Most VFD's take 120 or 240 input and have an output of 240.
 
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Thanks for the responses. Much appreciated. After posting this I did some more searching and found two pretty helpful videos on wiring this specific VFD.

Sharing in case someone comes across this in the future.

KBAC-27D
KBAC 27D


 
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