Rockwell Automation 20D PowerFlex 700S Drive Ph I Control, Frames 1...11 - Manual (Page 126)

3-72 Programming and Parameters
757 Abs Posit Offset
Provides an offset to absolute position. Setting Par 740 [Position Control], bit 8 [Xzero
Preset] presets Pars 744 [PositRef EGR Out], 747 [Position Cmmd], 763 [Act Motor Posit]
and 765 [Posit Actl Load] with the value in Par 762 [Mtr Posit Fdbk] minus Par 757 [Abs
Posit Offset] upon drive enable.
Default:
Min/Max: 0
-/+2147483648 ✓ ✓ 32-bit
Integer
758 Pt-Pt Posit Ref
Provides position reference to the point to point position regulator, when the value in Par
742 [Posit Ref Sel] equals 2 “Pt to Pt”. The initial value is latched upon position enable
without causing movement. Subsequent changes to reference are relative to the latched
position unless the position is re-referenced by Par 740 [Position Control], bit 10 [Pt-Pt
ReRef]. Position moves may be made within the limits of +/- 31 bits. Point to point
reference may be changed, and even reversed, during a move.
Default:
Min/Max: 0
-/+2147483648 ✓ ✓ 32-bit
Integer
759 Pt-Pt Accel Time
Acceleration time (sec) from zero to base speed, active only in point to point mode.
Acceleration to a relatively low speed may be exponential.
Units:
Default:
Min/Max: Sec
10.0000
0.1000/6553.5000 ✓ ✓ Real
760 Pt-Pt Decel Time
Deceleration time (sec) from base speed to zero, active only in point to point mode. Some
tailing can be expected at the end of a move as the drive comes into command position. It
is left to the user to select a time that does not place the drive in current or torque limit.
Deceleration from relatively low speed may be exponential.
Units:
Default:
Min/Max: Sec
10.0000
0.1000/6553.5000 ✓ ✓ Real
761 Pt-Pt Filt BW
Sets the bandwidth of a low pass filter which affects smoothness at the start of
deceleration in the point to point mode. A high filter bandwidth will produce a more square
deceleration torque, one with a higher level of jerk. Typical values range from 5 to 100
(rad/sec). A zero value will bypass the filter. Tail-out is influenced mainly by Par 768
[PositReg P Gain].
Units:
Default:
Min/Max: R/S
25.0000
0.0000/500.0000 ✓ ✓ Real
762 Mtr Posit Fdbk
Displays the accumulated pulse count of the primary feedback device as a 32 bit integer.
The primary feedback device is selected by Par 222 [Motor Fdbk Sel].
Default:
Min/Max: 0
-/+2147483648 32-bit
Integer
763 Act Motor Posit
Displays the accumulated motor position as a 32 bit integer. It tracks Par 762 [Mtr Posit
Fdbk]. When the position regulator is not enabled, this parameter is initialized to Par 762
[Mtr Posit Fdbk] or to the selected position reference as determined by Par 740 [Position
Control] bit 6 [ActPosit Rst].
Default:
Min/Max: 0
-/+2147483648 32-bit
Integer
764 Posit Load Fdbk
Tracks the load position as a 32 bit integer. When a gear box connects the load to the
motor, Par 766 [Posit FB EGR Mul] and Par 767 [Posit FB EGR Div] must be set to
account for the gear ratio. Set Par 766 [Posit FB EGR Mul] equal to Par 767 [Posit FB
EGR Div] if the load is directly connected to the motor.
Default:
Min/Max: 0
-/+2147483648 ✓ ✓ 32-bit
Integer
765 Posit Actl Load
Holds the accumulated output of the Load Gear Ratio as a 32 bit integer and forms the
primary feedback for the position regulator integral channel. It is very important that the
Load Gear Ratio be precisely set, such that the delta pulse count of one motor revolution
equals the delta pulse count of this parameter. When the position regulator is not
enabled, this parameter is initialized to Par 762 [Mtr Posit Fdbk] or to the selected position
reference as determined by Par 740 [Position Control] bit 6 [ActPosit Rst].
Default:
Mi/Max: 0
-/+2147483648 32-bit
Integer
766 Posit FB EGR Mul
A 32 bit integer in the numerator of the load Electronic Gear Ratio function. It is multiplied
by Par 764 [Posit Load Fdbk] and divided by Par 767 [Posit FB EGR Div] to reflect the
load pulse count to the motor (effectively removing the gear box ratio). The accumulated
position values of Par 763 [Act Motor Posit] and Par 765 [Posit Actl Load] 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 ✓ ✓ 32-bit
Integer
767 Posit FB EGR Div
This is a 32 bit integer that forms the denominator of the load Electronic Gear Ratio
function.
Default:
Min/Max: 1
1/2000000 32-bit
Integer
No.
Name
Description
Values Li
nkab
le
Read
-Wr
it
e
Da
ta
T
ype
762
Mtr Posit Fdbk
747 Position Cmmd
765 Posit Actl Load
+
-
757
Abs Posit Offset
740 8
Position Control
(Xzero Preset)
763 Act Motor Posit
744 PositRef EGR Out