
5.I/O SIGNALS B-63494EN/02
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5.1 OVERVIEW
The dual check safety function provides two input paths and two
output paths for safe-related signals (safety signals).
For input signals (safety input signals), two paths are used: one path
for input to the CNC via the PMC, and the other for input to the
monitor via the FSSB. The CNC and monitor exchange the safety
input signals with each other at all times to check each other. If a
mismatch is found between a safety input signal via one path and the
same signal via the other path, the signal is assumed to be 0. If such a
state lasts for the period set in a parameter or more, the CNC and
monitor independently detect an alarm. (Dual-check for safety input
signals)
For output signals (safety output signals), two paths are used: one path
for output from the CNC via the PMC, and the other for output from
the monitor via the FSSB. The MCC-on enable signal (MCF) is output
via these two paths. When both a signal via one path and the same
signal via the other path are 1, the signal is assumed to be 1. If either
is 0, the signal is assumed to be 0. That is, if the signal (MCF1) via the
PMC and the signal (MCF2) via the FSSB are both 1, the MCC may
be turned on. If either is 0, the MCC must be turned off.
In Subsection 5.2, a signal name is followed by its symbol and
addresses <via PMC> and <via FSSB>. Then, for an input signal, its
classification, function, and operation are described, in this order. For
an output signal, its classification, function, and output condition are
described in this order.
For information about the emergency stop mode, MCC off Test mode,
and safety signal modes A/B/C/D described in Subsection 5.2, see
Section 5.4.
Section 5.3 provides a list of the addresses of related signals for
1-CPU 1-path control, 2-CPU 2-path control, 1-CPU 2-path control,
2-CPU 3-path control, and loader control in this order.