This feature is available on the following drives (AKD Models). The hardware control card and revision number can be read with DRV.INFO. The following control cards are active in production since 2016. Newer drives of these types will continue to have this functionality.
- AKD sercos® III
- Drive type NBCC or NBEC: control card 105-200801-01, all revisions
- AKD PDMM: control card 105-200400-01, revision V and greater
- NBCN or NBAN: control card 105-200101-01, all revisions
Use the initial position check to determine whether homing is required at power-up. The initial position check compares the difference between the position it measures at power-up with a position stored in fast non-volatile memory (FB1.INITPSAVED) before the last power-down. The parameter FB1.INITPSTATUS will read whether the position difference is within an acceptable user defined window (FB1.INITPWINDOW).
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- This function only checks a real physical move outside of the window. A position overrun, which can occur in certain applications, is not detected and will not lead to an outside window status.
Example 1
In this example, the window is set to 10 degrees and the status reports that the position is within the window (precondition).
-->FB1.INITPWINDOW 10
-->FB1.INITPSTATUS
2
Now the axis is powered down and moved slightly during power down time:
The values after a full power cycle:
--> FB1.P
12472.839 [PIN/POUT]
--> FB1.INITPWINDOW
10.000 [PIN/POUT]
--> FB1.INITPSAVED
12469.221 [PIN/POUT]
--> FB1.INITPSTATUS
2
The axis has only moved a few degrees physically, and is still within the configured window.
Example 2
Now the axis is moved farther while powered down.
After power up, the axis is outside the window:
FB1.INITPSTATUS will now report 3 (outside window).
--> FB1.P
12531.269 [PIN/POUT]
--> FB1.INITPWINDOW
10.000 [PIN/POUT]
--> FB1.INITPSAVED
12472.833 [PIN/POUT]
--> FB1.INITPSTATUS
3
