Rockwell Automation 21G PowerFlex 750-Series AC Drives Programming Manual - Manual (Page 70)

70 Rockwell Automation Publication 750-PM001J-EN-P - October 2014
Chapter 3 Drive Port 0 Parameters
FEEDBA
CK & I/O
Feedback
136 Load Psn FdbkSel
Load Position Feedback Select
Selects a position load feedback source for the position control. The position load
feedback P847 [Psn Fdbk] indicates the selected position feedback value. The value
forms the primary feedback for the position regulator integration channel.
Default:
Min/Max: 847
1 / 159999 RW 32-bit
Integer
137 Open Loop Fdbk
Open Loop Feedback
An estimated motor feedback source that is available to any of the Velocity Feedback
Selection parameters – P125 [Pri Vel Fdbk Sel], P128 [Alt Vel Fdbk Sel], and P132 [Aux
Vel Fdbk Sel]. Open Loop Feedback is not available as a Position feedback source.
The Open Loop Feedback’s parameter value has units of encoder counts as established by
P141 [Virtual Enc EPR]. Open Loop feedback is estimated based on P1 [Output
Frequency] and P5 [Torque Cur Fdbk], adjusted using P621 [Slip RPM at FLA]. Default:
Options: 0
–2147483648 / 2147483647 RO 32-bit
Integer
138 Simulator Fdbk
Simulator Feedback
Simulator Feedback is a calculated motor feedback source. It can be used when
operating in any of the Flux Vector control modes that are selected in P35 [Motor Ctrl
Mode]. Simulator Feedback is available to any of the Velocity Feedback Selection
parameters: P125 [Pri Vel Fdbk Sel], P128 [Alt Vel Fdbk Sel], and P132 [Aux Vel Fdbk Sel].
Simulator Feedback is also available as a Position feedback source as selected by P135
[Psn Fdbk Sel].
The Simulator Feedback’s parameter value has units of encoder counts, as established by
P141 [Virtual Enc EPR]. Simulator velocity feedback is calculated based on P690 [Limited
Trq Ref] and P76 [Total Inertia]. This selection is useful for drive operational checkout
and test when motor movement is undesired. In simulation mode, gating of the power
inverter section of the drive is disabled. Default:
Options: 0
–2147483648 / 2147483647 RO 32-bit
Integer
139 Delayed Spd Ref
Delayed Speed Reference
One sample period delayed output of P594 [Ramped Spd Ref]. Used in some
applications to synchronize the speed reference value when controlling multiple drives.
In these applications, the drive that supplies the master speed reference would use the
[Delayed Spd Ref] value. Setting P635 [Spd Options Ctrl] Bit 8 “Delayed Ref” will select
the delayed reference in the master drive. P594 [Ramped Spd Ref] would then be
transmitted to the slave drives over a communication link.
Units:
Default:
Min/Max:
Hz
RPM
0.00
–/+P27 [Motor NP Hertz] x 8
–/+P28 [Motor NP RPM] x 8 RO Real
140 Virtual EncDelay
Virtual Encoder Delay
One sample period delayed output of P142 [Virtual Enc Psn]. Used in some applications
to phase synchronize position reference though a drive communications link. The master
is delayed one sample while the downstream drives update their position references –
then all drives sample position simultaneously. The downstream drives do not select a
delay. The selection of the delayed or non-delayed position reference is made by
choosing the desired parameter in P766 [Psn Direct Stpt].
Default:
Options: 0
–2147483648 / 2147483624 RO 32-bit
Integer
141 Virtual Enc EPR
Virtual Encoder Edges Per Revolution
Equivalent Edges Per Revolution (EPR) or line count of a virtual encoder. A virtual
encoder is a position reference whose input is derived from the speed reference. It
accumulates pulses at the same rate as a real encoder of identical Pulses Per Revolution
(PPR). Enter the equivalent PPR. For example, enter 1024 PPR to match an encoder with
1024 EPR.
Default:
Min/Max: 4096
10 / 67108864 RW 32-bit
Integer
142 Virtual Enc Psn
Virtual Encoder Position
A 32 bit pulse accumulator of the virtual encoder. The accumulated pulse count is
equivalent to the hardware accumulator of a real encoder. It accumulates at a rate of 4x
the value placed in P141 [Virtual Enc EPR]. The accumulator starts at zero upon position
enable.
Default:
Min/Max: 0
–2147483648 / 2147483647 RO 32-bit
Integer
Fi
le
Grou
p
No. Display Name
Full Name
Description Values
Re
ad
-W
ri
te
Da
ta
T
ype
755
755
755
755
755