Subject to technical modifications, no responsibility is accepted for the accuracy of this information. © EUCHNER 2016
AP000152-05_03/16
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Safety assessment
The CET3 features complete monitoring for faults in the safety-relevant parts and in the connected cables (clock pulses at outputs
OA and OB). The safety relay PNOZ s5 achieves up to PL e according to the manufacturer’s information (see the device’s operating
instructions for this purpose). The wiring corresponds to the circuit “Light beam device or safety switch with detection of shorts
across contacts via ESPE” in the operating instructions of the PNOZ s5. Therefore, PL e in accordance with EN ISO 13849-1 can
be achieved for locking mechanism position monitoring of guard locking of the CET3. Series connection of three CET3 devices
does not reduce the achievable PL.
A safety assessment for control of guard locking is not part of this example and must be supplemented for the respective machine
by the design engineer in accordance with the risk assessment.
Important: Switch-off of the energy and any necessary monitoring energy switch-off (feedback loop) of the hazard are not part of
this document and must be added in accordance with the risk assessment for the machine. In this example, the safety evaluation
unit without feedback loop and without start button is used. Please refer to the operating instructions of the safety evaluation unit
used for more information.