Operation; 8�1 Switching State Of The Outputs; 8�1�1 The Safe State; 8�1�2 The Switched State - Reer PI M18 NF Manual De Instrucciones

8 Operation

8.1 Switching state of the outputs
8.1.1 The safe state
The safe state is when at least one of the outputs A1 or A2 (OSSDs) is switched
off (zero-current state: logic "0")�
If one of the outputs A1 or A2 is switched off, the subsequent safety-related logic
unit must bring the complete system into the state defined as safe�
8.1.2 The switched state
If the damping element is in the enable zone and if there is no sensor error, both
outputs A1 and A2 (OSSDs) are enabled (logic "1")�
8.1.3 Output characteristics
The output characteristics are compatible with the input characteristics to
EN 61131-2 type 1 or 2:
Logic "1"
Logic "0"
The interface corresponds to interface type C class 1 according to the ZVEI
position paper "Klassifizierung binärer 24-V-Schnittstellen mit Testung im Bereich
der Funktionalen Sicherheit" (Classification of binary 24V interfaces tested with
regard to functional safety)�
8.1.4 Cross fault / short circuit
• A cross fault between both outputs (A1 and A2) is detected by the fail-safe
sensor and results in the outputs (OSSD) being switched off at the next safety
request� The outputs A1 and A2 remain switched off until the error has been
removed or a voltage reset has been carried out�
• A cross fault (short circuit) between output A2 and the supply voltage results in
the other output A1 being switched off in case of a safety request�
• When there is no current flow on the output stage, back feeding > 3�5 V will
lead to malfunction�
• The device carries out self-tests for the switch-off capability on A2�
≥ 15 V
≥ 11 V
≤ 5 V
2���15 mA
15���30 mA
leakage current 0�2 mA
UK
9