The question has risen of using solid wires for the 18 - 22 gauge twisted shielded pairs for the master alarm panel signal wires.
The only thing I find in the NFPA 99, 2018 is the verbiage referencing how the wires are to be run (protected, cable trays, conduit, etc.).
The only area where wiring specifically come in to NFPA 99, 2018 is the section stating all medical gas components shall be installed per manufacturer's installation instructions.
Good, I buy that. Then, I see a manufacturer's instructions and the issue of stranded vs. solid is not there!
What am I missing here??????
I had this thought stranded wires would be best due to the nature of the alarms are all components monitored are Normally Closed indicators.
Wouldn't solid wire, if broken, be an issue? Or, if the solid breaks then a stranded wire would break also give the same circumstances?
I have seen solid wire cause errant alarms.
Please enlighten me to what I am missing or am I much ado about nothing!!???
