Hi,

I have an ACS550 that I have an issue that when I press the run forward or jog forward, the motor chatters and runs in the wrong direction at very low speed about 26 RPM when the command speed is 1800 RPM. If I jog the motor in reverse then jog or run forward the drive starts at command speed. It should be noted that I have the motor set for a min speed of 300RPM and max 1800 RPM. This is like the motor doesn't start correct at zero speed. I have also tried adjusting parameter 2112 zero speed on and off but it does not help. I am controlling the drive from the I/O but have also done test from the keypad and I have the same issue.


I am running in Vector: Torque mode. I spoke to ABB Canada and they suggested I set parameters 2606 = Linear, 2619 = enable. I have also set 2015 and 2017 min/max torque to -600%/+600% which I think is really not necessary as this happen if the motor is coupled or uncoupled from the load. I also set 2005 = 0 to enable the brake resistor of 75 ohm 1000W. The motor driving a lathe spindle. I am not using encoder feedback.

The firmware in the drive is;
3301 = 0x316B
3302 = 0x1002
Any help in this is greatly appreciated.

I tried to upload a short video but the size is to large at 2.4MB

 

Running in Vector Torque Control mode without encoder feedback can lead to stability issues, especially during low-speed operation. If encoder feedback isn't used, switching to Scalar (V/Hz) mode or Vector Speed Control (open loop) might be better.

 

Yes this is what I have done switched to Vector Speed. If I find I still need the torque (this is a high torque application) I will add the encoder.

 

I actually also have another problem with this drive. Sometimes when I jog or run the drive it trips on fault code 1, over-current. As suggested I have increased the ramp parameter. The fault happens even when not coupled to the load, I am starting to think the drive is defective.