Kmg problems

Guindesigns

Well-Known Member
So today was the first day I've been able to work in the shop all day for a while. While working my kmg just shut down on me. I felt the motor and it was hot!! So I'm letting it cool over night. But don't remember them having a function to turn off when to hot. Could I have a bigger issue??
 
I wouldn't be surprised if it is thermally protected. Were you doing anything that might cause it to get hot?
 
If you have a 3 phase motor and VFD running it slow will heat motor up and may trip thermal protection on motor if so equipped.
 
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Yeah if it was hot in the shop it's very plausible that it tripped out.

Make sure the fan is attached and clean, assuming it is a TEFC. They can work loose and get plugged with enough dust to stop moving much air.
 
After cooling all night I plugged it back in and flipped the switch anddd....nothing.. then I began to play with the reset switch something click into place and BAM!!!! It was running full steam ahead!!!
I'm give it a good cleaning and just keep an eye out for how hot it is from now on. I have to get me a better shop fan also.
 
IS this the 3 speed KMG with pulleys and a TEFC 1ph motor? What HP is the motor? How were you grinding - really bearing down hogging metal that puts a heavy load on motor? OR, light grinding? As mentioned if the fan has came loose and not cooling would cause the motor to overheat. If an open frame motor crud can get inside and need blowing out.

Good luck - and as you mentioned, a VFD and 3 ph motor makes all the difference in the world. I used a 3 speed pulley setup for 2 or 3 yrs and thought that was all I needed. Once I got a 2hp 3ph TEFC motor and VFD (total cost $245) I wondered why I didn't make the move years ago. Yes, it's a NEMA 1 Chinese VFD, but with filters over the air inlets they tend to last for years.
 
IS this the 3 speed KMG with pulleys and a TEFC 1ph motor? What HP is the motor? How were you grinding - really bearing down hogging metal that puts a heavy load on motor? OR, light grinding? As mentioned if the fan has came loose and not cooling would cause the motor to overheat. If an open frame motor crud can get inside and need blowing out.

Good luck - and as you mentioned, a VFD and 3 ph motor makes all the difference in the world. I used a 3 speed pulley setup for 2 or 3 yrs and thought that was all I needed. Once I got a 2hp 3ph TEFC motor and VFD (total cost $245) I wondered why I didn't make the move years ago. Yes, it's a NEMA 1 Chinese VFD, but with filters over the air inlets they tend to last for years.
Yes it's the 3 spd pulley. I have been flirting with the idea of getting a 4 step pulley's but haven't made my mind up yet. I know I have a VFD with the bigger motor but don't have the power capacity right now in my shop.
 
Understand the power problems. I did the 4 step pulley for more speeds also. Power issues are something that's hard to get around. I wish there were Chinese suppliers of VFD with 120/240 vac input and 230 vac 3ph output, but the only VFD I find is the KBAC KBDA-27D for $389. https://www.amazon.com/dp/B01AOCKQ2A/ This drive would allow you to run your 2hp 3 ph motor on 120vac input (at 1.5hp rating), then when you do get 240 vac input you're set for full 2hp (which is only used in heavy hogging).
 
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