IEEE 384:2018 pdf free download – IEEE Standard Criteria for Indepen dence of Class 1E Equipment and Circuits
5.1.8.3 Routing requirements
The routing of Class 1E or associated circuit cables or raceways in fire hazard areas shall conform to thefollowing requirements:
a)Where the fire hazard source involved is qualified for design basis events, is not assignable to a single division, and the fire requires no protective action; Class 1E or associated circuit cables or racewaysrouted through the area shall be limited to a single division.
b) Where the effect of the fire hazard requires protective action, Class 1E or associated circuit cables orraceways shall not be routed through the area, except those cables that must terminate at devices orloads within the area.
NOTE—Special provisions (such as additional system redundancy or diversity) may be required for these cablesto meet the single failure criterion.
c) Where the fire hazard source involved is qualified for design basis events,is assignable to a singledivision, and protective action is not required; Class 1E or associated circuit cables or raceways routedthrough the area shall be limited to the same division as the fire hazard.
d) Where the fire hazard source involved is not qualified for design basis events, Class 1E or associated circuit cables or raceways shall not be routed in the area except for those cables that must terminateat devices within the area. Where Class 1E or associated circuit cables and raceways are routed in theareas that have been classified as hazard areas due to non-nuclear safety-related fire hazard sources,they shall be protected from that area by the methods in 5.1.8.2 or the fire hazard source shall bequalified for design basis events.
5.1.9.1 General
Fiber-optic circuits have no potential to degrade other fiber-optic or current carrying circuits; therefore, thereare no separation requirements for a faulted fiber-optic circuit as a source cable. Separation criteria in 5.1.9.2for fiber-optic circuits are only applicable for fiber-optic circuits that are target cables.Additionaldiscussion offiber-optic circuits is provided in Annex C.
5.1.9.2 Separation distances
No separation distance is required between Class 1E fiber-optic circuits of one division and Class 1E fiber-optic circuits of a redundant division.No separation distance is required between non-Class 1E and Class 1Efiber-optic circuits.
For interactions between fiber-optic circuits as target cables and current carrying circuits as source cables,separation distances are different than that specified in 5.1.3 and 5.1.4 because of the different performancecharacteristics.For nonhazard and limited hazard areas, the minimum separation distances for Class 1E fiber-optic circuits requiring separation per Clause 4 are identified in Table 3.This table includes four columns thatprovide minimum distance criteria based on the types and sizes of the current carrying circuit cables involvedin each interaction. Fiber-optic circuits shall have a minimum temperature rating of 40°C(104°F).
6.2.1 General
Electrical isolation methods shall be used as required in instrumentation and control circuits to maintain theindependence of redundant circuits and equipment such that safety functions required during and followingany design basis event can be accomplished. This electrical isolation of instrumentation and control circuitsshall be achieved through the use of Class 1E isolation devices applied to interconnections of 1)Class 1E andnon-Class 1E circuits,2) associated circuits and non-Class 1Ecircuits, or3)Class 1Elogiccircuits of redundantdivisions, as shown in the examples in Figure 8.Shielding and wiring techniques may also be necessary toachieve and maintain the independence of redundant circuits and equipment.EMI/RFl interactions shall alsobe considered as discussed in 4.11.
Refer to IEEE Std 690 for definitions of instrumentation and control cables.