PDA

View Full Version : Ultra3000i Current Limiting

OkiePC
December 19th, 2006, 02:53 PM
Greetings!

We have a small conveyor made up of metal bins that catch product with an indexing motion. It is controlled by an Ultra3000i indexing servo drive. Today, a technician told me that he has never seen the drvie fault, even when the conveyor gets in a serious bind, it just rips itself apart.

He asked me to try to limit the drive current so that it would fault rather than create so much damage. I found a cable and fired up the laptop with Ultraware, connected to the drive and found the only place I could adjust any current setting was under the "Faults" branch "user current limit". The value in the drive was 255 amps! The drive/motor tab showed a peak current limit of 32amps.

I monitored the drive in normal operation and found the peak current to be 9 amps. I set the user current limit to 15 amps for now. I am not sure if what I did will help. Apparently, the bins on this conveyor come loose and hang up on the frame at least once a week so I should find out soon enough.

Can anyone tell me if I adjusted the correct parameter?

Thanks,
Paul
mgvol
December 19th, 2006, 03:03 PM
I do believe that is right. BTW, I just opened a "dummy" ULTRA 3000 project in Ultraware, and it looks as if 255A is the default.
agarb
December 19th, 2006, 03:53 PM
Wrong spot. Double-click on the drive in workspace and change the current limits.

http://www.plctalk.net/qanda/uploads/ultra3k.jpg

By changing the "User Current Fault", I suspect you will make more work for yourself. Everytime it happens, you'll have to come out and hook up to the drive to clear the fault.

By the way, I couldn't find the Current Limits the first time I looked for them. I had to call A/B.
Gerry
December 19th, 2006, 03:55 PM
You should also look at the position error settings.
OkiePC
December 19th, 2006, 04:00 PM
Thanks guys, I will get right on it...can I change those settings online? while running?
Or must I stop the drive and/or download?
agarb
December 19th, 2006, 04:06 PM
It's been awhile since I messed with an Ultra3000, but you should be able to do it online. Just becareful to save your settings properly. (By dragging the on-line drive to the off-line drive.) This is very non-intuitive.
OkiePC
December 19th, 2006, 04:07 PM
...Just becareful to save your settings properly. (By dragging the on-line drive to the off-line drive.) This is very non-intuitive.
Yeah, I spent nearly an hour figuring that out the one other time I have been online with one of these drives...thanks again...Paul