Siemens SIMATIC S7-1500 Manual page 22

Digital inputs DI0 and DI1
The digital inputs are used for gate control, synchronization and the Capture function.
The digital inputs of the two channels are not isolated from one another.
Input delay for digital inputs
You can use this parameter to suppress signal noise at the digital inputs of a channel.
Changes to the signal are only detected if they remain stable for longer than the configured
input delay time.
Note
If you select the "None" or "0.05 ms" option, you must use shielded cables for connection of
the digital inputs.
Digital outputs DQ0 and DQ1
The digital outputs of the two channels are not isolated from one another.
The digital outputs are 24 V sourcing outputs in reference to M and can carry a rated load
current of 0.5 A. They are protected against overload and short-circuit.
Relays and contactors can be directly connected without an external protective circuit. You
can find information on the maximum possible operating frequencies and the inductance
values of the inductive loads connected to the digital outputs in section Technical
specifications (Page 82).
Technology module TM PosInput 2 (6ES7551-1AB00-0AB0)
Manual, 06/2018, A5E03982218-AB
Wiring
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