Safety Function And Safe State - Pepperl+Fuchs K-LB Series Manual

Functional Safety K-LB-*.*, F*-LB-I, P-LB-*.*.*
Planning
3.3

Safety Function and Safe State

The surge protection barrier has to be considered in conjunction with the connected field
device. The safety function of the surge protection barrier is defined by the signals and settings
of the connected device (e. g. isolator, DCS input, output, field device).
Safety Function
The safety function of the device is to behave like a piece of copper wire, passing through
the process signal without being altered. In case of a 0/4 mA to 20 mA signal the maximum
additional loop current fault of the device is maximum ± 1 % full scale.
Safe State
The safe state is defined as the device interrupting the input signal.
Reaction Time
The reaction time is < 20 ms.
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