1 Scope
This part of IEC 60079 contains the details of apparatus, systems and installation practice for use with
the Fieldbus Intrinsically Safe Concept (FISCO). It is based on the concepts of Manchester
encoded, bus powered systems designed in accordance with IEC 61158‑2 which is the physical layer standard for Fieldbus installations.
The constructional and installation requirements of FISCO apparatus and systems are
determined by IEC 60079‑11, IEC 60079‑14, and IEC 60079‑25, except as modified by this standard. Part of a Fieldbus device may be protected
by any of the methods of explosion protection listed in IEC 60079‑0, appropriate to the zone of intended use. In these circumstances, the requirements
of this standard apply only to that part of the apparatus directly connected to the
intrinsically safe trunk or spurs.
NOTE 1 Certification to the FISCO requirements does not prevent apparatus also being certified
and marked to IEC 60079‑11 in the conventional manner so that they may be used in other systems. Some apparatus
certified before this standard was published but not necessarily complying with the
electrical parameters of this standard may be marked “Suitable for FISCO systems”.
This apparatus may be accepted in a FISCO system, if the comparison of the electrical
parameters U o , I o , P o , with U i , I i , P i , demonstrate compatibility with the remainder of the system, and all the other requirements
of this standard are met.