Time For Short-Circuit Test; Startup Time Of Sensor After Short-Circuit Test - Siemens SIMATIC ET 200SP Equipment Manual

4.2.2.2

Time for short-circuit test

Function
When the short-circuit test is enabled, the corresponding sensor supply is switched off for the
configured time. If the module does not detect a "0" signal at the input within the assigned
time, a diagnostic message is generated.
Note the following during parameter assignment:
• If the channel is passivated, this may be due to too high capacitance between sensor
supply and input. This consists of the capacitance per unit length of the cable and the
capacitance of the employed sensor. If the connected capacitance does not discharge
within the assigned time, you need to adjust the "Time for short-circuit test" parameter.
• The values available for the input delay depend on the "Startup time of sensor after short-
circuit test" and the "Time for short-circuit test" of the configured sensor supply.
Requirement
The short-circuit test is activated.
4.2.2.3

Startup time of sensor after short-circuit test

Function
Apart from the switch-off time ("Time for short-circuit test"), a startup time must also be
specified for the execution of the short-circuit test. With this parameter you inform the
module how long the used sensor requires for the startup after the sensor supply is switched
on. This way you avoid an undefined input status due to transient responses in the sensor.
Note the following during parameter assignment:
• This parameter must be larger than the settling time of the sensor used.
• Since the parameterized time affects the response time of the module, we recommend
setting this time as short as possible but large enough so that the sensor has stabilized.
• The values available for the input delay depend on the "Startup time of sensor after short-
circuit test" and the "Time for short-circuit test" of the configured sensor supply.
Requirement
The short-circuit test is activated.
Note
Dependencies between the parameters "Startup time of sensor after short-circuit test"
and "Time for short-circuit test"
The startup time of the sensor after the short-circuit test must amount to at least 1 % of the
time for the short-circuit test.
Digital input module F-DI 8x24VDC HF (6ES7136-6BA01-0CA0)
Equipment Manual, 10/2021, A5E50578307-AA
Parameters/address space
4.2 Explanation of parameters
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