Safety engineering
Device modules
Safe inputs
29
EDS94AYAF EN 1.0
1.2.5
Safe inputs
1.2.5.1
General
The following applies to the sensors on the SM302:
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The sensor type and function can be parameterised.
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A local evaluation is executed if corresponding parameters are set.
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If a safety bus is activated, the sensor signals are sent as status information to the
higher−level control.
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Deactivated sensor inputs must not be connected. The status of a non−connected
input is OFF.
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If a signal is detected at deactivated sensor inputs during initialisation, the drive
remains inhibited (STO).
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Faulty inputs are assessed as OFF state.
Specification
Sensor type
passive
active
Discrepancy time
parameterisable 0 ... 30000 ms (increment: 2 ms)
Input delay
parameterisable 0 ... 100 ms (increment: 2 ms)
Input filter time for test pulses
fixed 2 ms
Repetition rate of the test pulses
is determined by the clock outputs
CLA and CLB
> 50 ms
Error response
Sensor input is assessed as OFF state.
Acknowledgement via safety bus or AIE input
Tab. 1−2
Specification of sensor connections
Explanations
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Discrepancy time
Maximum time in which both channels of a safe input may have non−equivalent states
without the safety engineering causing an error response.
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Input delay
Time between the recognition of the signal change and the effective evaluation of an
input signal. As a result, multiple and short signal changes due to contact bounce of the
components are not taken into account.
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Input filter time
Time in which the interference pulses and test pulses are not detected by e.g. active
sensors that are switched on.
The input delay time and the time of the input filters influence the response time. More
information can be found in the "Response times" chapter (