Rockwell Automation SP600 AC Drive User Manual Version 1.0 - Manual (Page 30)

2-16 SP600 AC Drive User Manual
Disabling Dynamic Mode will cause the drive to operate in Normal
Mode and parameter values will be transferred from operating
memory into the active non-volatile storage area.
2.4.20 Process PI Loop
The internal process PI function provides closed-loop process
control with proportional and integral control action. The PI function
reads a process variable input to the drive and compares it to a
desired setpoint stored in the drive. The algorithm will then adjust
the output of the process PI regulator thereby changing drive output
frequency to try to make the process variable equal the setpoint.
Refer to the descriptions of parameters 124 to 138 in chapter 12 for
more information.
2.4.21 S Curve
The S Curve function of SP600 drives allows control of the "jerk"
component of acceleration and deceleration through adjustment of
the S Curve parameter (146). Jerk is defined as the rate of change
of acceleration and/or deceleration. By adjusting the percentage of
the S Curve applied to the normal accel/decel ramps, the ramp
takes the shape of an "S" allowing a smoother transition that
produces less mechanical stress and smoother control for light
loads.
2.4.22 Three Skip Bands (Avoidance Frequencies)
The skip band function (see parameters 84 to 87 in chapter 12)
provides three skip bands (also called avoidance frequencies) that
the drive will ramp through but will not continuously run within. You
can set the skip frequency (center frequency) and bandwidth of
each band. This function is used to avoid mechanical resonance
operating setpoints.
Figure 2.3 – Dynamic Mode Operation