Siemens SIMATIC S7-300 FM 350-1 Manual page 89

Commands for the Counting Modes
You can apply five commands to the FM 350-1 counting process during operation:
Table 7- 4 The FM 350-1 commands
Name
Open and close gate
Setting the counter
Latch/retrigger
Latch
Measure times between two
edges
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
Description
The counting process starts when a gate opens and ends when it closes.
The counter can be set to the load value using various signals.
Saves the counter level and loads the counter with the load value in response to a
positive edge at DI Start.
Saves the counter level in response to a positive edge at DI.Start.
Measures the times between two immediately successive edges at the DI Start digital
input.
Operating Modes, parameters and commands
7.3 Count modes
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