SIRIUS ACT 3SU1 pushbuttons and signaling devices
System Manual, 08/2018, A5E03457306020A/RS-AK/010
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ATEX for intrinsically safe circuits
Type of protection "i" - intrinsic safety
The intrinsic safety of a circuit is achieved by safe restriction of the energy taking faults into
consideration.
● No thermal ignition (temperature rise)
● No spark ignition (closing / opening sparks).
Suitable applications are found, for example, in measuring and control engineering.
The basis for the "intrinsically safe" protection type is that a specific minimum ignition energy
is required to ignite a potentially explosive atmosphere. In an intrinsically-safe circuit, no
sparks or thermal effects occur in operation or in the event of a fault that ignite a potentially
explosive atmosphere.
Intrinsic safety is divided into various levels of protection: ia, ib and ic.
● Based on standard: IEC 60079-11, IEC 60079-0
The mounting specifications from the system manual are to be observed. Only in this way
are the safety function and the conformity with the guideline for explosion protection
maintained.
Note: Requirements from standards IEC 60079-0; IEC 60079-11; IEC 60079-14; IEC 60079-
17; IEC 60079-19; IEC 60079-25
Simple electrical equipment (gas/dust atmosphere)
From our portfolio of pushbuttons and indicator lights, actuators, contact modules, empty
enclosures and special accessories have been classified according to the requirements
(IEC 60079-11: 2011, Para. 5.7 Simple apparatus) and are thus suitable for use in
intrinsically safe circuits.
: Siemens Confirmation No.: 3287
(
https://support.industry.siemens.com/cs/document/109476838/confirmation-
manufacturer?dti=0&lc=en-WW)