Rockwell Automation SP600 User Manual Version 3.0 - Manual (Page 26)

2-12 SP600 AC Drive User Manual
2.3.20 S Curve
The S Curve function of SP600 drives allows control of the "jerk"
component of acceleration and deceleration through user
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 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.
Refer to the description of parameter 146 in chapter 11 for more
information.
2.3.21 Three Skip Bands (Avoidance Frequencies)
The skip band function (see parameters 84 to 87 in chapter 11)
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.
2.3.22 Flying Start
The flying start feature (enabled in parameter 169) is used to start
into a rotating motor as rapidly as possible and resume normal
operation with a minimal impact on load or speed. This action will
prevent an overcurrent trip and significantly reduce the time for the
motor to reach its desired frequency. Since the motor is "picked up"
smoothly at its rotating speed and ramped to the proper speed, little
or no mechanical stress is present.
Refer to the description of parameter 169 in chapter 11 for more
information.
2.3.23 Voltage Class
The voltage class (see parameter 202 in chapter 11) identifies the
general input voltage to the drive. This general voltage includes a
range of actual operating voltages. A 400 volt class drive will have
an acceptable input voltage range of 380 to 480 VAC. A 575 volt
class will have a range of 475 to 632 volts.
While the hardware remains the same within each class, other
variables, such as factory defaults and power unit ratings, will
change. In most cases, all drives within a voltage class can be
reprogrammed to accommodate a motor within its voltage class.
This can be done by resetting the Voltage Class parameter to a
different setup within the voltage class.