Siemens SIMATIC S7-1500 System Manual page 117

Configuring
7.9 Configuration of digital inputs/outputs (X142)
Note
Unsupported instructions for X142
The function blocks for the use of time-based IO (TIO instructions) are not supported by the
X142 interface.
Recommendation: Use the measuring input technology object for timer DI.
Adjustment for measuring range activation time
● To adjust the activation time defined in the system, enter an additional activation time in
the Extended parameters configuration window.
Lost Edge Counter (LEC)
Timer DI support Lost Edge Counter. If more than two edges to be detected occur within one
position control cycle, a measured value cannot be evaluated for the other edges to be
detected. The LEC records the number of edges lost.
Which lost edges are recorded in the LEC depends on the mode set in the Motion Control
instruction. For example, if you only want to measure rising edges, the LEC only records the
rising edges not measured. The LEC can count and display a maximum of seven lost edges.
The number of lost edges is displayed in the function block and in the technology data block.
Further information
You can find additional information on the following topics in the S7-1500T Motion Control
function manuals (https://support.industry.siemens.com/cs/ww/en/view/109751049):
● Measuring input type: Timer DI
● Measuring input type: SINAMICS (central measuring input)
● Measuring input type: PROFIdrive telegram (drive or external encoder)
● Lost Edge Counter (LEC)
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SIMATIC Drive Controller
System Manual, 11/2019, A5E46600094-AA