KBDA-29(1p) Startup Issue

I don't have that controller, so this may not help... However, I was setting up a new VFD for my Bridgeport last night and ran into a bit of trouble. It wasn't running like it should. After poking around a bit, I realized there is a parameter labeled "Rated motor frequency". The default was 400Hz. No idea why as I've never seen a motor that wanted that high of a frequency. Changing it to 60Hz made it run great at all the speeds I wanted it to run at, about 20-100Hz. My VFD is a Chinesium special, so your nicer unit might not need something this simple.

On the KBDA drive they come from the factory with the native Hz set at 60Hz and then the user can change to 50Hz if need be.

KB Electronics technical support has been amazing. The engineer who has been helping me has gone out of his way to find a solution. He had me try many different parameter settings and I had a direct line to him for communicating back and forth. During the troubleshooting I sent him video of all the different configurations we tried and he finally came to the conclusion that the motor I have is not fully compatible with that drive. Mostly due to being a 3600 rpm motor. Apparently the KBDA drive doesn't do what he called "dead time compensation" which affects some 3600 rpm motors. I believe this is something they are working on to improve. This affects my motors behavior from about 40Hz to 55Hz. He said it will work fine with a 1800 rpm motor. The bad news is my belt grinder design is based on a 3600 rpm motor so getting another 3600 rpm motor has a good chance of not working. That left me with looking for another drive controller.

I was blown away this morning when I got a call from KB Electronics wanting my address so they could send me another drive controller that will work with my motor at no cost. Their only stipulation was that I call them back and let them know how it works. I get to keep the drive controller I already have to use for another project. WOW!

The drive that will work with the 3hp 3600 rpm motor is the KBCA-29(1p). It's not digital with a key pad but I'm not complaining.
 
Nice to see that level of support, much better than I have experienced with a few other VFD manufactures. I have had some combinations of VFDs and motors that just wasn't a good fit no matter what I tried, mostly 2 speed motors (not constant Hp ones). I like the sealed KB units but I have had programming and braking limitations for the type of systems I have worked with. One thought would be to go with an 1800 RPM motor and push it up to 120Hz for high speed grinding. Would have better low end torque and Hp at the slower speeds. The Baldor has a 6000 rpm top speed.
Deleted the WEG listed it was footless, but there are other inverter motors that should easily go to 3600 RPM Teco is a good choice and cost effective.
https://www.ebay.com/itm/TECO-Max-E...0014-1-HP-1745-RPM-230-460V-143T/182489426107
https://www.ebay.com/itm/BALDOR-1-HP-3-PH-INVERTER-DRIVE-MOTOR-NEW/191731639588

Note: Can't use these KB drive for 120Hz, most are 60 Hz max +10% if I recall.
 
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That's how I run my grinder motor. It's an 1800 run 20-120Hz. With the wheels I have, the belt runs fast enough that I don't use the highest setting much.
 
Nice to see that level of support, much better than I have experienced with a few other VFD manufactures. I have had some combinations of VFDs and motors that just wasn't a good fit no matter what I tried, mostly 2 speed motors (not constant Hp ones). I like the sealed KB units but I have had programming and braking limitations for the type of systems I have worked with. One thought would be to go with an 1800 RPM motor and push it up to 120Hz for high speed grinding. Would have better low end torque and Hp at the slower speeds. The Baldor has a 6000 rpm to speed.
https://www.ebay.com/itm/WEG-00118E...-143-TC-Encl-TEFC-Inverter-Motor/113014134886
https://www.ebay.com/itm/BALDOR-1-HP-3-PH-INVERTER-DRIVE-MOTOR-NEW/191731639588

Hmmm.....those are 1hp motors? I'm running 3hp.

To get the SFM I want with an 1800 rpm motor I would need to increase the drive wheel size which changes the geometry of the drive system. Currently I am locked into a 3600 rpm 182T frame motor unless I make physical changes to the grinder frame which is built and painted.

I should have the new drive early next week and see how it goes.
 
For informational purposes here is a video of the best we could get my motor to run with the KBDA drive.

 
:faint: My mistake, I am use to seeing smaller motors on these drives, usually 1-1.5Hp. The motor seems to have vibration modes and seems to shudder from ~55-40 Hz, should be silky smooth. Better to try a new drive first, would be curios to see how the analog KB drive works. If a new motor, I have had good success with the inverter rated Baldor, Marathon, Teco and Lincoln. OK some 3Hp motors, 4 Pole. The first is $100 plus shipping if you need to go that route. I guess this is not your typical portable sander....
https://www.ebay.com/itm/TECO-WESTI...HH8P-FRAME-182T-230-460V-1755RPM/282893388247
https://www.ebay.com/itm/NEW-MARATH...864455?hash=item46744c3e47:g:fdcAAOSw4HNaV4MF
https://www.ebay.com/itm/Marathon-1...3-Phase-Hazardous-Location-Motor/232725006158
 
I have that same E470 Marathon motor on my lathe. Very nice motor. The motor I have was a trade so I'm sticking with it for now. We'll see how it goes with the other KB drive.
 
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