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10 Operation
10.1 Switching state of the outputs
The safety light grids have two outputs (OSSDs); the status depends on the
condition of the protected area�
Any short circuits between the outputs or between an output and the operating
voltage (24 V DC or 0 V DC) are detected by the safety light grids as a fault�
Output
Binary states
Description
OSSD1
1
Condition
Protected area clear�
OSSD2
1
OSSD1
1
0
0
Condition
Protected area interrupted or fault detected�
OSSD2
0
1
0
10.1.1 The safe state
The safe state is when at least one of the outputs (OSSDs) is switched off (zero-
current state: logic "0")�
If one of the outputs is switched off, the subsequent safety-related logic unit must
bring the complete system into the state defined as safe�
10.1.2 The switched state
In switched state the active element provides a current of 24 V DC (logic "1") to
both outputs�
Output characteristics
The output characteristics follow the characteristics of the input according to
IEC 61496:
Logic "1"
24 V DC
max� 500 mA
Logic "0"
≤ 1.5 V DC
< 0�2 mA
10.1.3 Interface classification
The interface of the devices complies with interface type C class 3 according to
the ZVEI position paper CB 24I Ed� 2�0
Identification key
Interface type
Suitable interface type
Source
C3
Receiver
C1
C2
C3
