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Entry type: FAQ, Entry ID: 45147736, Entry date: 09/15/2010

SIRIUS 3RA6 Reversing Starter with AS-i Mounting Module: Local Safety Shutdown at SIL 1 due to IEC 62061 / PL c due to EN ISO 13849-1:2006

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How can I use the local inputs of the AS-i mounting module of the 3RA6 reversing starter?

What safety category can be achieved by means of the local inputs of the AS-i mounting module?


One example is the monitoring of the limit position of a conveyor belt.
SIL 1 according to IEC 62061 resp. PL c according to
EN ISO 13849-1:2006 (in the following ISO 13849-1) can be achieved.

Based on the functional safety standards IEC 62061 and ISO 13849-1 it is possible to perform a qualitative and quantitative assessment of safety functions with non-safety-related (standard) components.

Examples of such non-safety-related (standard) components are the switching and protection devices of the SIRIUS Innovation series. These devices are frequently used in applications aimed at the protection of assets.

This FAQ describes how two position switches with a positively-opening contact can be monitored by using the local inputs of the AS-i mounting module, so as to initiate the safe shutdown of the 3RA6 at level SIL 1 according to IEC 62061 or PL c according ISO 13849-1 or category 2 according to EN 954-1. Operation of the position switch will cause the 3RA6 compact feeder to disconnect. In this example, a drive unit will be shut down.

The machine under consideration uses a drive to move a lifting mechanism to two defined conveyor levels. The drive is controlled by means of a compact feeder type RA62 (reversing starter). The pick-up and place-down positions of the lifting unit are monitored in automatic mode with the help of proximity switches. These proximity switches are registered and analyzed by the SIMATIC controller. For the purpose of servicing and maintenance, the stop positions effective in automatic mode can be exceeded. In the setup mode, however, the upper and lower limit positions are monitored by mechanical position switches for the reason of machine safety. This disconnection at the end position of the lifting drive is then effected through direct analysis of the position switches at the local inputs of the AS-i mounting module. This direct shutdown becomes also effective when an incident occurs (e.g. failure of one proximity switch).


3RA6_lokale_Abschaltung_rechts_links_Lauf_EN_FAQ_45147736.pdf ( 313 KB )

( 28 KB ) 3RA6_Wendestarter_71838.set ( 28 KB )

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