Parker 406LXR Series, Product Manual

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Parker Hannifin Corporation
EMN Automation - Parker
Irwin, Pennsylvania
30
406LXR Series Product Manual Chapter 4 - Performance
Non - Slope Corrected Error Plot, Total error 48µm
Note: Slope Factor is 200 µm /m in this example.
correction in the variable equation, or if your controller has floating decimal scaling (with high enough
precision) the slope correction can be accounted for in scaling.
NOTE: The zero position (or starting point) of the error plots are at the extreme NEGATIVE end of
travel (refer to Chapter 2, Dimensional Drawing , for Negative end location).
Slope Corrected Error Plot, Total error 8.5µm
Slope Corrected Error Plot
-4
-2
0
2
4
6
0
20 40 60 80
100 120 140 160 180 200 220 240
Positions (mm)
Er
ro
r
(Mi
c
ro
n
s
)
Non-Slope Corrected Error Plot
0
10
20
30
40
50
60
0
20 40 60 80
100 120 140 160 180 200 220 240
Positions (mm)
Er
ro
r
(Mi
c
ro
n
s
)
Example:
Below is a sample program showing how to correct for slope error using variables. This example
program will work with the 6K as well as the 6000 Series Parker Controllers.
Step 2 through 3 of this program should be made a subroutine. This subroutine can then be executed
for each distance.
Step 1
VAR 1 = 1280; IN THIS CASE THE DESIRED DISTANCE IS 1280mm.
Step 2
DEL SLCORR ; DELETE SLCORR PROGRAM
DEF SLCORR ; DEFINE SLCORR PROGRAM
VAR 2 = (VAR1/1000)* (0.085); VAR2 EQUALS DESIRED DISTANCE (IN METERS) TIMES THE
SLOPE FACTOR (mm/meter)
Step 3
VAR 3 = ( VAR 1 - VAR 2); SUBTRACT SLOPE ERROR FROM DESIRED DISTANCE
Step 4
D ( VAR 3); SET DISTANCE AS VAR3
END ; END SUBROUTINE
In the example above, the required move distance is 1280 mm. But the LXR has a slope error of
0.085mm per meter. This is a positive slope error meaning that if uncorrected the LXR will move 0.085
mm too far for every meter it travels. To correct we must command a smaller position.
Step 1: The required move distance is set as variable #1.