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38 SAFETY DEVICES, SAFETY LABELS, AND CONSTANTS
38.1 Safety Devices
Safety counter (SA\C)
This device counts the number of rising operation of the input condition in the program. The safety counter is an up-timing
type device and therefore when the count value matches a setting value, the count reaches its upper limit and the contact is
turned on. Operations other than the following are the same as those for the counter. ( Page 344 Counter)
■Safety counter types
There is a safety counter (SA\C) that retains the counter value in 16-bit units.
■Counting process
When the safety counter coil is executed, the safety counter coil is turned on/off, the current value is updated (count value +1),
and the contact is turned on/off. The current value is updated (count value +1) when the safety counter coil input is rising (off
to on). The current value is not updated when the coil input is off, on to on, and on to off.
■Resetting the safety counter
The safety counter current value is not cleared even when the counter coil input is turned off. To clear (reset) the safety
counter current value and turn off the contact, issue the RST SA\C instruction. When the RST SA\C instruction is
executed, the counter value is cleared and the contact is turned off.
Safety data register (SA\D)
This device can store numerical values.
Safety link register (SA\W)
This device is used as a device when sending and receiving safety data between SIL2 Process CPUs over CC-Link IE Field
Network.
■Refreshing network modules using safety link register
Data is sent and received between SIL2 Process CPUs. The safety communications send/receive device range is set in the
CC-Link IE Field Network safety communication settings. Locations that are not used for safety communications send/receive
devices can be used for other applications.
: Safety cycle processing start
K10
OFF
ON
ON
OFF
SA\X0
SA/C0
[Ladder example]
OUT SA/C0 OUT SA/C0 OUT SA/C0
[Current value update timing]
Safety program
SA/X0
SA\C0 (coil)
The current value is updated. The current value is updated.
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