Siemens SIMATIC S7-1500 Equipment Manual page 12

Principle of operation
The module counts the switching cycles by evaluating the rising edges of an output signal. If
the module detects a rising edge, the switching cycle counter (24-bit) for the respective
channel is incremented. After an overflow of the switching cycle counter, it starts again with
0.
If you activate the "Maintenance switching cycles" parameter, the "Limit warning" of the
maintenance interrupt is triggered when the limit is exceeded. Alternatively, activate the
maintenance alarm in the parameter data records starting at DS 64.
The current counter states are stored on the module cyclically (approx. every 20 seconds) and
retentively. The switching cycle counters are reset each time the module is restarted (power
off/on).
You activate the function with the "Switching cycle counter" parameter or in the parameter
data sets starting at DS 64.
You can read the current counter states with data set DS 129. Data set DS 129 contains the
counter status for each channel in UDINT format.
You can read the limits for each channel in UDINT format with data set DS 130.
Data set DS 131 enables you to overwrite the current counter value for each switching cycle
counter.
You can set a limit for each switching cycle counter with the "Switching cycle limit" parameter
or with data set DS 131.
Digital output module DQ 8x230VAC/2A ST Triac (6ES7522-5FF00-0AB0)
Equipment Manual, 12/2021, A5E03485733-AE
Product overview
2.2 Functions
11