Rockwell Automation ArmorStart Bulletin 280G, User Manual

Page: 312 / 324

H-4 PID Setup
PID Preload
The value set in Parameter 239 (PID Preload), in Hertz, will be pre-
loaded into the integral component of the PID at any start or enable.
This will cause the drive’s frequency command to initially jump to
that preload frequency, and the PID loop starts regulating from there.
PID Limits
Parameter 230 (PID Trim Hi) and Parameter 231 (PID Trim Lo) are
used to limit the PID output and are only used in trim mode. (PID
Trim Hi) sets the maximum frequency for the PID output in trim
mode. (PID Trim Lo) sets the reverse frequency limit for the PID
output in trim mode. Note that when the PID reaches the Hi or Lo
limit, the PID regulator stops integrating so that windup does not
occur.
PID Gains
The proportional, integral, and differential gains make up the PID
regulator.
• Parameter 234 (PID Prop Gain)
The proportional gain (unitless) affects how the regulator reacts
to the magnitude of the error. The proportional component of the
PID regulator outputs a speed command proportional to the PID
error. For example, a proportional gain of 1 would output 100%
of maximum frequency when the PID error is 100% of the
analog input range. A larger value for (PID Prop Gain) makes
the proportional component more responsive, and a smaller
value makes it less responsive. Setting (PID Prop Gain) to 0.00
disables the proportional component of the PID loop.
PID Enabled
Freq Cmd
PID Output
PID Pre-load Value
PID Pre-load Value > 0