Allen-Bradley PowerFlex 525 User Manual

Rockwell Automation Publication 520-UM001G-EN-E - September 2014 221
PID Set Up Appendix F
2. Adjust the integral gain (leave the proportional gain set as in Step 1). After
a step change in the PID Feedback:
– If the response is too slow (see Slow Response – Over Damped
on
page 221), or the PID Feedback does not become equal to the PID
Reference, decrease A462 or A474 [PID x Integ Time].
– If there is a lot of oscillation in the PID Feedback before settling out
(see Oscillation – Under Damped
on page 221), increase A462 or
A474 [PID x Integ Time].
3. At this point, the differential gain may not be needed. However, if after
determining the values for A461 or A473 [PID x Prop Gain] and A462 or
A474 [PID x Integ Time]:
– Response is still slow after a step change, increase A463 or A475 [PID x
Diff Rate].
– Response is still unstable, decrease A463 or A475 [PID x Diff Rate].
The following figures show some typical responses of the PID loop at different
points during adjustment of the PID Gains.
Unstable Response
Slow Response – Over Damped
Oscillation – Under Damped
PID Feedback
PID Reference
Time
PID Feedback
PID Reference
Time
PID Feedback
PID Reference
Time

Allen-Bradley PowerFlex 525 Specifications

General

Horsepower	0.5-30 HP
kW	0.4-22 kW
Input Voltage	200-240V AC, 380-480V AC
Enclosure	IP20, NEMA/UL Type 1
Communications	EtherNet/IP
Control Methods	V/Hz, Sensorless Vector
STO	Safe Torque Off (STO)
Output Voltage	0-Input Voltage
Operating Temperature	-20°C to 50°C (-4°F to 122°F)
Storage Temperature	-40°C to 85°C (-40°F to 185°F)
Relative Humidity	5-95% non-condensing
Dimensions	Varies by model
Weight	Varies by model