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NFPA 70 NEC Fire Alarm wire and conduit question

NFPA 70 NEC Fire Alarm wire and conduit question

NFPA 70 NEC Fire Alarm wire and conduit question

(OP)
NEC 760 goes over the type of cable that can be used for low voltage fire alarm systems, namely FPL, FPLR, FPLP (Plenum) and the CMP wire types. Most Fire Alarm systems currently are using low voltage 24 VCD so the wiring is POWER LIMITED. Electrical Contractors are telling  me that their interpretation of NEC says that they can use THHN on their fire systems. I cannot find the reference to this, can the Electrical Contractors install THHN and still meet code?  Others tell me that when wire is installed in conduit it does not need to be fire rated. Is that true? From our interpretation of NEC we don't see that conduit is required on low voltage systems although it is prudent to protect the wire.

RE: NFPA 70 NEC Fire Alarm wire and conduit question

(OP)
I kept looking on this one and this is what I have found, please let me know if you have additional input.  CONDUIT is not required if you installed low voltage power limited circuits with FPL, FPLR, FPLP or CMP wire. If you use THHN wire it must be in conduit from Chap 3 methods for non-power limited cable. NEC Article 760 deals with both non power limited and power limited.

THHN - In conduit

FPL, FPLR, FPLP, CMP not required in conduit but special mounting requirements apply.

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