Siemens SIMATIC ET 200SP Manual page 21

You can connect the following encoders or sensors at inputs A, B and N:
● Sourcing output:
● Sinking output:
● Push pull:
Input filter for 24 V encoder signals
To suppress interferences, you can configure an input filter for the counting inputs A, B and
N. The selected filter frequency is based on a pulse-break ratio of between 40:60 and 60:40.
This produces a set minimum pulse/break time. Signal changes with a duration shorter than
the minimum pulse/break time are suppressed.
You can specify the following values for the filter frequency:
Table 3- 2
Filter frequency
100 Hz
200 Hz
500 Hz
1 kHz
2 kHz
5 kHz
10 kHz
20 kHz
50 kHz
100 kHz
200 kHz (default)
Digital inputs DI0, DI1 and DI2
There are three digital inputs. The digital inputs are used for gate control, synchronization
and the Capture function. Alternatively, you can use one or more digital inputs without the
mentioned functions and read the signal state of the respective digital input via the feedback
interface.
The digital inputs are not electrically isolated from each other.
Technology Module TM Count 1x24V (6ES7138‑6AA00‑0BA0)
Manual, 10/2013, A5E33002339-AA
The inputs A, B and N are switched by the encoder or sensor after 24VDC .
The inputs A, B and N are switched by the encoder or sensor after ground M .
The inputs A, B and N are switched by the encoder or sensor alternately after 24VDC and
ground M . Monitoring for wire break is possible with this type of encoder/sensor. The
wire break detection procedure (alternate switching) allows the counter value to change
in the event of an error (wire break) even without count pulses until the wire break is
detected.
Filter frequency and respective minimum pulse/break time
Minimum pulse/break time
4.0 ms
2.0 ms
800 µs
400 µs
200 µs
80 µs
40 µs
20 µs
8.0 µs
4.0 µs
2.0 µs
Wiring
3.1 Pin assignment
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