Siemens SIMATIC ST-1500 Function Manual page 50

2.2 Basics of counting, measuring and position input (TM Count, TM PosInput, Compact CPU)
Setting between comparison value and low limit
The low limit corresponds to the position value "0".
The digital output is set to 1 if:
0 <= position value <= comparison value
The comparison event is independent of the direction of the position value change.
Setting between comparison value 0 and comparison value 1
The comparison event can be configured for the digital output DQ1 if "Use by user program"
has been configured for the digital output DQ0.
DQ1 is set to 1 if:
Comparison value 0 <= position value <= comparison value 1
The comparison event is independent of the direction of the position value change.
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
The basics of counting, measurement and position detection
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