Position regulator step types – Rockwell Automation 20A PowerFlex 70EC/700VC User Manual
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Position Indexer/Speed Profiler
Parameter Level
Note: A negative number in the [Step X Value] will transition when the comparison is less than the [Step X Dwell].
Position Regulator Step Types
Encoder Incremental (Encoder Incr) - This is a move increment from the current
position in the direction, distance and speed programmed. When started the drive
ramps to the desired velocity, holds the speed, then ramps to zero speed at the
position desired within the tolerance window.
The example below shows a five step profile. The first three are “Encoder Incr
steps” followed by an “Encoder Abs” step to zero then an “End” step. For each
“Encoder Incr” step the drive ramps at [Step X AccelTime] to [Step X Velocity] in
the direction of the sign of [Step X Value] then decelerates at the rate of [Step X
DecelTime] to the position programmed in [Step X Value] which sets the desired
units of travel for the step. When the value programmed in [Step X Value] is
reached within the tolerance window programmed in [Encoder Pos Tol], the “At
Position” bit is set in [Profile Status]. In this example a dwell value held each of the
first three steps “At Position” for 1 second. After the [Step X Dwell] time expires
the profile transitions to the next step. The absolute step is used to send the profile
back to the home position. This is done by programming [Step 4 Value] to zero.
Step # Step X Type
Step X
Velocity
Step X
AccelTime
Step X
DecelTime
Step X
Value
Step X
Dwell
Step X
Batch
Step X
Next
1
Param Level 100
0.5
0.5
701
10.00
1
2
2
Param Level 200
0.5
0.5
701
20.00
1
3
3
Param Level 300
0.5
0.5
701
30.00
1
4
4
Encoder Abs 400
0.5
0.5
0.00
1.00
1
5
5
End
N/A
N/A
0.5
N/A
0.00
N/A
N/A
13
18
23
28
33
43
48
53
0
5
10
15
20
25
30
Step 1 Dwell Level, 725
Step 2 Dwell Level, 735
Step 3 Dwell Level, 745
Step 2
Step 1
Step 3
Time
Step 4
Step 5
-50
-150
-250
-350
-450
50
150
250
350
[Encoder Speed], 415
[Units Traveled], 701
Current Step
[Profile Status], 700
58
38
8
En
c
o
d
e
r Sp
e
e
d
Units Traveled
Profile Status (Scaled)
Current Step