
B–62073E–1/042. INTERFACE BETWEEN CNC AND PMC–NA OR NB
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(a) Manual reference position return selection signal (ZRN)
[Classification]
Input signal
[Function] This signal selects manual reference position return. Manual reference position return is a
kind of continuous manual feed. Therefore, to select manual reference position return, it is
required that the continuous manual feed mode be selected and that the manual reference
position return selection signal be set high.
When automatic operation and manual operation are done simultaneously, manual refer-
ence position return cannot be performed.
[Operation] When the manual reference position return selection signal goes high, the control unit func-
tions as described below.
i. If continuous manual feed selection J is low, the control unit ignores the manual reference
position return selection signal.
ii. If simultaneous automatic/manual operation is in progress, manual reference position re-
turn is not permitted. As a result, manual operation is assumed not to be selected. Auto-
matic operation continues.
iii. If manual operation is in progress, manual reference position return is enabled. In this
case, manual reference position return selection check signal MZRN goes high.
NOTE If the ZRN status changes from low to high or high to low during continuous manual feed, the
feedrate is decelerated to 0, then it is accelerated to a specified feedrate for manual reference
position return or continuous manual feed. The operation continues at that feedrate. During
that time, the feed axis direction selection signal may remain high.
(b) Manual reference position return selection check signal (MZRN)
[Classification]
Output signal
[Function] This signal reports that manual reference position return has been selected.
[Output Condition]
This signal goes high when:
– Manual reference position return has been selected.
The signal goes low when:
– The selection of manual reference position return has terminated