Reer Aus X Series Use And Maintenance

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CONTROL UNIT SERIES AUS X4 8540643 - 26/08/2016 Rev.13NEW SAFETY PARAMETERS FOR TYPE 2 BARRIERS ANDMANDATORY LABELLINGWith the publication of Edition 3 of the harmonized EN 61496-1standard it is no longer possible to use a Type 2 safety light barrierfor safety functions assessed as SIL 2 / PL d.If a safety level of SIL 2 / PL d (or higher) is required and it isnevertheless intended to use a safety light barrier, then it will benecessary to use a Type 4 safety light barrier.This regulatory requirement derives from the fact that the reduction ofrisk that can be obtained via a photoelectric safety barrier is not onlya function of the safety level of its electronic parts, but is alsodetermined by its systematic capabilities (for example:environmental influences, EMC, optical performance and detectionprinciple).The systematic capability of a Type 2 photoelectric barrier may in factnot be sufficient to ensure adequate risk reduction for SIL 2 / PL dapplications.The standard also establishes that the labelling of Type 2 safetybarriers must indicate such limitation to SIL 1 / PL c.The PFHd values declared for the electronic control part of thedevice, on the other hand, are not limited and therefore it is possibleto use the PFHd value provided by the manufacturer of the device inthe global assessment of the safety function, even if it exceeds theSIL 1 / PLc range.