Recommendation? Help me run a light off 220v vfd

I wanted to offer some advice to the OP.
That actuator will likely not hold up. There is a reason that most of the actuators in the 900N range are about three times that price. You get what you pay for, and in knifemaking tools normally you should pay for quality.
Also, you will want a lift type actuator that can support the weight it lifts. A light weight linear actuator often moves things back and forth but does not necessarily support much weight when inactive. The only way they work with much weight is with a scissors jack type lift system.

The motor you linked specs say 9 amps at 230VAC, that is only 2.5HP. A 3HP motor would draw 11+ amps. As I said earlier, you should take the listed ratings on these Chinese goods as wishful thinking. My guess is it delivers a bit less than 2.5HP.

The motor you linked is a 2-pole motor. A four-pole motor running at around 1750RPM will be a better choice. Use the 2X jumper in the VFD for high speed. You will slow the grinder down much more than speed it up. You get better slow speed control with a four-pole motor.

That is a 3HP motor (or so they say). Are you really going to need 3HP??? Will your VFD handle it? You said you have a KBAC-29. That is a 2HP motor drive and if run off single phase input only delivers 6.7amps. If you have a KBAC 29-1P, then it will derate a 3HP motor (assuming the motor really is a 3HP).

I assume you have big enough wiring and breaker for the grinder and other things running off that breaker. From what you have described, I would suggest you need a 220 30Amp breaker and "10-3 with ground" wire to the outlets. That will solve most of your electrical issues. Sometimes it is wisest to bite the bullet and do it right.
 
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Stacy E. Apelt - Bladesmith said:
I wanted to offer some advice to the OP.
That actuator will likely not hold up. There is a reason that most of the actuators in the 900N range are about three times that price. You get what you pay for, and in knifemaking tools normally you should pay for quality.
Also, you will want a lift type actuator that can support the weight it lifts. A light weight linear actuator often moves things back and forth but does not necessarily support much weight when inactive. The only way they work with much weight is with a scissors jack type lift system.

The motor you linked specs say 9 amps at 230VAC, that is only 2.5HP. A 3HP motor would draw 11+ amps. As I said earlier, you should take the listed ratings on these Chinese goods as wishful thinking. My guess is it delivers a bit less than 2.5HP.

The motor you linked is a 2-pole motor. A four-pole motor running at around 1750RPM will be a better choice. Use the 2X jumper in the VFD for high speed. You will slow the grinder down much more than speed it up. You get better slow speed control with a four-pole motor.

That is a 3HP motor (or so they say). Are you really going to need 3HP??? Will your VFD handle it? You said you have a KBAC-29. That is a 2HP motor drive and if run off single phase input only delivers 6.7amps. If you have a KBAC 29-1P, then it will derate a 3HP motor (assuming the motor really is a 3HP).

I assume you have big enough wiring and breaker for the grinder and other things running off that breaker. From what you have described, I would suggest you need a 220 30Amp breaker and "10-3 with ground" wire to the outlets. That will solve most of your electrical issues. Sometimes it is wisest to bite the bullet and do it right.
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The motor seems to work awesome so far, I can make it run faster than I would ever actually need it without the 2x jumper in the vfd and I've tested it by grinding some thick steel and really shoving it in there and it didn't bat an eye or slow in any way.

I did't think to add the 1p for the kbac 29, which looking at it now wouldn't matter because on the website all kbac-29s go up to 3hp, but yes, I made sure it was made for a 3hp motor, and it is 220 input only.

The only reason I went with 3 is because the price difference was negligable, as stated before, and why not? If it's a little over powered then who cares? I'd rather that than to bog it down and regret not going bigger.
 
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I edited an error in my post.

If you look at the chart on page 7 of the manual, you will see that the KBAC-29 only handles 2HP on single phase input.
This is note #4 - KBAC-29: Rated 2 HP maximum with 1-phase AC Line input and 3 HP maximum with 3-phase AC Line input.

I suspect the internal overload protection circuit in the VFD is derating the 3HP motor to 2HP because it only delivers a max of 6.7 amps. You wouldn't be aware of it because you have no real idea of how much power is generated. The RPM is the same. See paragraph 4.3 on page 6 of the manual.

I did not realize you already bought the items you were asking about. I guess it is all moot now.

Yes, your grinder runs plenty fast, but that is because it is a two-pole motor running at around 3500RPM. With a two-pole motor you don't need or want the 2X jumper.
It is the slower speeds that will give you less from the VFD on a two-pole motor. A four-pole motor has more torque, which prevents stalling at slow speed. The 2-pole vs 4-pole debate is a long running one and for most folks it doesn't matter, but there is a difference.

Not diminishing your build at all, just offering some technical things you may not have been aware of. It may not change anything for you, but someone reading this may have additional information when they select drives and motors.
 
Stacy E. Apelt - Bladesmith said:
Craig, he only has 220 on the wall. He needed 110.

His best solution would be to run a new line down the wall with 110 and 220 outlets, but he says he isn't doing that yet.
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what if he puts two lamps in series, that would make it according to ohms law :) more light is always good!

Pablo
 
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