Current / speed curve, Current/speed – Rockwell Automation 20P PowerFlex Digital DC Drive User Manual
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Rockwell Automation Publication 20P-UM001I-EN-P - February 2013
Appendix C
Application Notes
•
Par 1045 [Anlg In1 Cmp Eq] = “1” (high) when the signal on Analog
Input 1 is within the range specified in Par 1043 [Anlg In1 Cmp Err]. Par
1045 [Anlg In1 Cmp Eq] = “0” (low) when the signal on Analog Input 1 is
outside the range specified in Par 1043 [Anlg In1 Cmp Err].
Example 2:
An application requires an indication via a digital output that the output current
is within ±2% of 50% of the maximum current limit.
•
Par 7 [Current Limit] = 100% (maximum reference value)
•
For Analog Input 1, 10V or 20mA sets the maximum value = Par 7
[Current Limit]
Configure the following:
•
Set Par 70 [Anlg In1 Sel] = “Pos Cur Lim”
•
Set [Digital Outx Sel] = “Input1 Cmp” (Par 1045 [Anlg In1 Cmp Eq])
•
Set Par 1042 [Anlg In1 Cmp] = 5000 (50 x 10000 / 100)
•
Set Par 1043 [Anlg In1 Cmp Err] = 200 (2 x 10000 / 100 )
Current / Speed Curve
The current/speed curve function allows you to establish a current limit lower
than the standard current limits of the drive (specified in parameters 8 [Current
Lim Pos] and 9 [Current Lim Neg]) and reduce the output current (torque) of
the drive through a defined curve of five equally divided set points as the speed
increases based on a threshold speed, effectively reducing torque.
Par 10 [Cur Lim Pos Out]
or
Par 11 [Cur Lim Neg Out]
Par 751 [TrqTpr Lim0]
Current/Speed
Par 162 [Max Feedback Spd]
Par 752 [TrqTpr Lim1]
Par 753 [TrqTpr Lim2]
Par 754 [TrqTpr Lim3]
Par 755 [TrqTpr Lim4]
Par 756 [TrqTpr Spd]
Curr
en
t
Speed