Multiple Skip Speeds - Allen-Bradley Kinetix 5700 User Manual

Appendix E Motor Control Feature Support
416

Multiple Skip Speeds

The Kinetix 5700 drives feature two independent skip-speed attributes
(SkipSpeed1 and SkipSpeed2) that use the same SkipSpeedBand.
Figure 219 - Multiple Skip Speed Example
SkipSpeed2
SkipSpeed1
0
0
When skip-speed band boundaries of SkipSpeed1 and SkipSpeed2 overlap, the
skip-speed hysteresis is calculated using the effective skip band.
In Figure 220, SkipSpeed1 is set to 0 and SkipSpeed2 is set to 15 hz. The skip
band is 10 Hz wide.
At point A the axis is enabled, and the motor begins to rotate at -5 Hz even
though the command is 0 Hz. As the command reaches hysteresis point the
output frequency begins to follow the command. During deceleration, when
the command decreases to 0 Hz, the output frequency continues at 5 Hz until
the axis is disabled (point B), or the command is changed outside of the skip
band.
Figure 220 - Zero-speed Skip Frequency
30
25
20
15
10
5
A
0
-5
-10
0 5000 10,000
Output Frequency
Rockwell Automation Publication 2198-UM002G-EN-P - February 2019
SkipSpeedBand
SkipSpeedBand
Time
SkipSpeed1 = 0 Hz
SkipSpeed2 = 15 Hz
Skip Band = 10 Hz
B
15,000 20,000 25,000 30,000
Command Frequency
35,000 40,000