Rockwell Automation 21G PowerFlex 750-Series AC Drives Programming Manual User Manual
Page 145

Rockwell Automation Publication 750-PM001J-EN-P - October 2014
145
Drive Port 0 Parameters
Chapter 3
Fil
e
Gr
ou
p
No.
Display Name
Full Name
Description
Values
Re
ad
-Write
Da
ta T
ype
POSITION C
O
N
TR
O
L
Po
si
ti
on
O
ffs
et
820
Psn Offset 1 Sel
Position Offset 1 Select
Selects a Position Offset 1 source.
Default:
Min/Max:
821
1 / 159999
RW 32-bit
Integer
821
Psn Offset 1
Position Offset 1
Provides position reference offset, which is summed after the EGR and used to trim the
phase of the position reference. A step in the offset position will be internally rate
limited and added to the reference position. The rate of correction is set by the offset
velocity P824 [Psn Offset Vel]. The initial value of this parameter is latched upon position
enable without causing a change in reference. Subsequent changes to this value will be
relative to the latched value. See the offset re-referencing bit P721 [Position Control] Bit
2 “Offset ReRef.”
Default:
Min/Max:
0
–2147483648 / 2147483647
RW 32-bit
Integer
822
Psn Offset 2 Sel
Position Offset 2 Select
Selects a Position Offset 2 source.
Default:
Min/Max:
823
1 / 159999
RW 32-bit
Integer
823
Psn Offset 2
Position Offset 2 Select
Provides another position reference offset, which is summed with P821 [Psn Offset 1]
and used to trim the phase of the position reference. The rate of correction is set by the
offset velocity P824 [Psn Offset Vel].
Default:
Min/Max:
0
–2147483648 / 2147483647
RW 32-bit
Integer
824
Psn Offset Vel
Position Offset Velocity
Sets speed of position offset. A position offset command will not exceed this speed. The
actual speed of offset is limited to a maximum value of 1/(inertia x pos gain) so as not to
cause a torque pulse greater than 1 per unit. The speed will change exponentially.
Units:
Default:
Min/Max:
Hz
RPM
P27 [Motor NP Hertz] x 0.005
P28 [Motor NP RPM] x 0.005
0.00/P27 [Motor NP Hertz]
0.00/P28 [Motor NP RPM]
RW Real
Fi
le
Grou
p
No.
Display Name
Full Name
Description
Values
Rea
d-W
ri
te
Da
ta
T
yp
e
POSITION
CONTRO
L
Ld
P
sn F
dbk S
cal
825
LdPsn Fdbk Mult
Load Position Feedback Multiplier
Sets numerator of the load EGR function. It is multiplied by the position load feedback
selected by the load feedback select P136 [Load Psn FdbkSel] and divided by the load
feedback divider P826 [LdPsn Fdbk Div] to reflect the load pulse count to the motor
(effectively removing the gear box ratio). The accumulated position values P836 [Psn
Actual] and the position load actual P837 [Psn Load Actual] - will be equal if the ratio is
set properly. There may be some difference due to lost motion in the gear train, but
there should not be an accumulated difference. It is often necessary to count gear teeth
as gear box manufacturers often approximate exact ratios with decimal numbers. Enter
a negative value in the numerator to account for reversed motor rotation.
Default:
Min/Max:
1
–/+1000000
RW 32-bit
Integer
826
LdPsn Fdbk Div
Load Position Feedback Division
Sets denominator of the load EGR function.
Default:
Min/Max:
1
1 / 2000000
RW 32-bit
Integer
755
755