Speed Reference Control - Allen-Bradley PowerFlex 70 User Manual

Appendix C Application Notes

Speed Reference Control

116
The actual output frequency at maximum speed reference is the sum of the speed
reference plus speed adder components from functions such as slip
compensation.
The Overspeed Limit is entered in Hertz and added to Maximum Speed and the
sum of the two (Speed Limit) limit the output frequency. This sum (Speed
Limit) must is compared to Maximum Frequency and an alarm is initiated that
prevents operation if the Speed Limit exceeds Maximum Frequency.
Allowable Output Frequency Range - Normal Operation 1
Maximum
Voltage
Motor NP
Voltage
Frequency Trim
due to Speed
Control Mode
Break
Voltage
Start
Boost
Run
Boost
0 Minimum Break
Speed Frequency
Note 1: The lower limit on this range can be 0 depending on the value of Speed Adder
"Auto" Speed Sources
The drive speed command can be obtained from a number of different sources.
The source is determined by drive programming and the condition of the speed
select digital inputs, Auto/Manual digital input or reference select bits of a
command word.
The default source for a command reference (all speed select inputs open or not
programmed) is the selection programmed in P90 [Speed Ref A Sel]. If any of the
speed select inputs are closed, the drive uses other parameters as the speed
command source.
If a communication device is the source of the speed reference, refer to the
appropriate communications manual for additional information.
Rockwell Automation Publication 20A-UM001N-EN-P - July 2013
Allowable Output Frequency Range -
Bus Regulation or Current Limit
Allowable Speed Reference Range
Motor NP Hz
Frequency
Overspeed
Limit
Maximum Output Maximum
Speed Frequency Frequency
Limit