Fire alarm wire is always solid

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If it's a tradition it's certainly a bad one. Speaker/strobe devices with an in and an out will need 8 conductors terminated on the device. Try shoving that into the box when the conductors are #14 and #12 solid.:roll:
 
I thought stranded wire had to be used.....and not fine stranded (either 12 or 19 strand??) instead of 7 strand.

At least that is how I remember it.
 
wireman said:
I thought stranded wire had to be used.....and not fine stranded (either 12 or 19 strand??) instead of 7 strand.

At least that is how I remember it.
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OOPS... Meant to say I thought FINE stranded wire HAD to be used.
 
iwire said:
I was watching one our guys do that and we hear a loud 'snap', the terminal strip broke off the PC board. :roll:
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I'm familiar with that sound, especially when the guy before you installed a box that's much too small. :)
 
wireman said:
OOPS... Meant to say I thought FINE stranded wire HAD to be used.
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Actually it was the other way in the older codes for non-power limited fire alarm wiring. 760-16(c) in the 90 code required that the conductors be solid or bunched tinned with an exception that permitted up to 7 strands for 16 and 18 gauge conductors and up to 19 strands for larger conductors. Not sure when this rule was removed from the code.
 
It is not an electrical necessarily. It is requirement in most specifications put out by A&Es. I am noticing that many A&E spec documents are based on older systems and requirements (mainly Simplex). For example I read one last week that called for electro-mechanical horns, stobes with an aluminum plate and white polycarbonate lens and spare bulbs.

For older Fire Alarm Systems, solid conductors were required for survivability before fire rated cables existed.

Today any cable listed as FPLP, FPLR,FPL, FPLP-CI, FPLR-CI, FPL-CL is acceptable for fire alarm system wiring 760.176, 760.179
 
TLBryant said:
It is not an electrical necessarily. It is requirement in most specifications put out by A&Es. I am noticing that many A&E spec documents are based on older systems and requirements (mainly Simplex). For example I read one last week that called for electro-mechanical horns, stobes with an aluminum plate and white polycarbonate lens and spare bulbs.

For older Fire Alarm Systems, solid conductors were required for survivability before fire rated cables existed.

Today any cable listed as FPLP, FPLR,FPL, FPLP-CI, FPLR-CI, FPL-CL is acceptable for fire alarm system wiring 760.176, 760.179
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That A&E spec is hilarious.

I know it's supposed to fpl, fplp etc. But a lot of individual conductors (THHN, THWN or TEWN). Is used in EMT around here. I know it's a technical violation, but it's almost universally accepted. Any one have thoughts on this?
 
TLBryant said:
...
For older Fire Alarm Systems, solid conductors were required for survivability before fire rated cables existed.
...
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The old code permitted up to 7 strands for 16 and 18 and up to 19 strands for larger conductors. My understanding of the reason for the rule was that with the higher current loads on the older fire alarm systems, a single strand strand in a 16 gauge with more than 7 strands would be able to carry the supervision current, but may not be able to carry the load of the alarm horns when the system was activated.
 
Nplfa

Nplfa

Chris can you help me out here? NPLFA is for high voltage fire alarm correct? Non Power Limited. The power limited is the most used Fire Alarm currently which is low voltage but NEC indicates that you can use FPL, FPLR or FPLP or (CMP) for power limited. I know that THHN is used quite often and exceeds the voltage requirement when it comes to the FPL but many systems require wire that has a certain amount of twists typlically 12 per foot for data transfer. The reference you give is for the older high voltage fire alarm systems? Please help me understand this.
 
Stranded Fire Alarm Wire

Stranded Fire Alarm Wire

760.49 NPLFA Circuit Conductors.

(C) Conductor Materials. Conductors shall be solid or stranded copper.

760.176 Listing and Marking of NPLFA Cables.

(A) NPLFA Conductor Materials. Conductors shall be 18 AWG or larger solid or stranded copper.


Just had an inspection today and was questioned why we used stranded wire. We were installing outdoor devices and ran some wire exposed (until a protective soffit could be built). I selected outdoor rated insulation for the job which came as stranded. I also read the code article above before the job began. In Vermont we use the 08 electrical and the 02 fire alarm codes.
 
The wire used depends on the specs of the job. the only time we use solid wire for NACs is if the job requires it specifically ( usually due to a plenum rated or riser rated jacketed cable or a free air wire scenario)
NACs are stranded 12 ga THHN. in some older buildings we see solid wire but we almost never use solid THHN for NAC circuits.
I work on a lot of old panels ( early 90s mid 80s some early 80s) and some panels are still 110 volt so thats why you see solid wire for both initiating and notification circuits.
If you are talking THHN wire we never use solid unless we are replacing a bad wire but if the wire is plenum or riser rated jacketed then its all solid.
This is in Los Angeles orange county area southern california
We use 08 NEC and NFPA
 
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