Reer PI M12 NF Notice D'utilisation Originale page 25

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