Parameters Of The Sensor Supply; Short-Circuit Test - Siemens SIMATIC ET 200SP Equipment Manual

Parameters/address space
4.2 Explanation of parameters
4.2.2

Parameters of the sensor supply

4.2.2.1

Short-circuit test

Here you activate the short-circuit detection for the channels of the F-module for which an
internal sensor supply is set.
The short-circuit test can always be performed when you use simple switches which do not
have an own power supply. For switches with an own power supply, e.g. 3-/4-wire proximity
switches or optical sensors with OSSD outputs (Output Signal Switching Device), you have to
adjust the parameter "Startup time of sensor after short-circuit test" depending on the sensor
used.
The short-circuit detection switches off the sensor supply briefly. The length of the
deactivation period is equivalent to the configured "Time for short-circuit test".
If a short-circuit is detected, the F-module triggers a diagnostic interrupt and the input is
passivated.
The following short-circuits are detected:
• Short-circuit of input to L+
• Short-circuit of the input with another channel, if this has a 1-signal
• Short-circuit between the input and sensor supply of another channel
• Short-circuit between the sensor supply and the sensor supply of another channel
If the short-circuit test is disabled, you must make your wiring short-circuit and cross-circuit
proof or select a connection type (discrepancy, non-equivalent) which also detect the cross-
circuits using discrepancy.
Note
During the execution time (Time for short-circuit test + Startup time of sensor after short-
circuit test) of the short-circuit test, the last valid value of the input before the start of the
short-circuit test is passed to the F-CPU. The activation of the short-circuit test thus affects the
response time of the respective channel or channel pair.
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Digital input module F-DI 8x24VDC HF (6ES7136-6BA01-0CA0)
Equipment Manual, 10/2021, A5E50578307-AA