Controllers
6.3 Safety concept ATD4xxW
AT40, ATD400V, ATD400K, ATD4xxW, ATD400S, ATE250S, ATD400T
System Manual, 06/2016, A2B00096162-AN
101
6.3.3.3
Frequency-based input signals
As well as 1oo2 evaluation with antivalent channels, a frequency-based system can also be
used to implement fail-safe inputs according to PLd.
Two frequency analysis blocks are available for this purpose, and can be linked to any input
channel. See Section Auto-Hotspot.
6.3.3.4
Two-hand operation concept (according to Cat. IIIA)
This concept describes implementation of two-hand operation in compliance with DIN EN
574:2008-12, Category IIIA. To achieve the specified Category IIIA, it is imperative that a
discrepancy time of ≤
500 ms be parameterized.
Note
Only Category I is possible with discrepancy times > 500 ms.
Where a two-hand control device is used, two sensors are routed to the SIDOOR controller
in a safety-related fashion and are internally evaluated via the "AND0" discrepancy analysis
block.
Antivalent connection of two redundant antivalent sensors to two channels
Two redundant antivalent sensors are needed for the signal (1oo2 evaluation)
Image 6-12 Two-hand control device example