Recommended Wire for Sensor Installation

scriptx

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I was searching for a recommended wire for sensor installation (magnetic reed window/door contacts), however I couldn't find exact recommendations. From everyone's experience, should I just go with two pair cable for the sensors, or 4 pair for the potential of an extra zone (e.g. glass break)? Would you recommend shielded wire paticular gauges or should I just pull Cat 5/6 for everything?
 
Everyone has their own opinions when it comes to cable, but I would run 22/2 for window and door sensors and 22/4 for glass breaks and motion sensors. You might want to look at our cable guide as well.

Sirens might require a smaller gauge size depending on its current requirements. I run the Moose Piezo's (very low current draw) and just use 22/2.

I also hate solid wire as it is not nearly as flexible as stranded, but other's have different opinions on this.

Belden is also a favorite cable brand.
 
I was searching for a recommended wire for sensor installation (magnetic reed window/door contacts), however I couldn't find exact recommendations. From everyone's experience, should I just go with two pair cable for the sensors, or 4 pair for the potential of an extra zone (e.g. glass break)? Would you recommend shielded wire paticular gauges or should I just pull Cat 5/6 for everything?
Most professionals 4/C #22AWG or 2/C #22 AWG CL2 rated wire. Code requires the CL2 rating, but Cat 5, which is rated as type CM, is an acceptable substiture for CL2. Cat 5 is AWG 24 which is too small and fragile to work with for alarm sensors in my opinion, plus, the extra conductors will just be in the way. I like the solid wire, as opposed to stranded, as it is so much easier to terminate, although it is somewhat more prone to breaking.
 
+1 on the 22AWG. I do it like BSR and use 22/2 on non powered contacts and 22/4 on powered devices like PIR and GB's. Some people like to just get 22/4 and use it for everything and thats acceptable, but I would not use Cat5 for sensors.
 
Do most people use fire-rated cable for smokes? I know best practice doesn't always jive with reality.

I think I've read of some people buying one box/reel of fire-rated cable, and using it for everything.
 
Do most people use fire-rated cable for smokes? I know best practice doesn't always jive with reality.

I think I've read of some people buying one box/reel of fire-rated cable, and using it for everything.


I found a user here that offered to sell me some of his extra as I only needed like 30 feet of it... but I only used fire cable for smokes
 
Fire rated cable is very expensive. So I can see using it to wire all my smokes and then using the excess on something else, but it would just be too expensive to use it everywhere. I'd also make doube sure that I had enough wire for all my smokes and heat detectors before I started using it for something else.

For example, my local supplier sells 500' of 18/4 firerated wire for $175 vs $37 for 500' of 22/4.
 
18/4 for smokes? No 22/4 fire-rated cable available?

Do hardwired LV smoke detectors possess alarms, or does the control panel signal the horn to alarm? Or both?

Should the sounder output(s), and telco, be connected with fire-rated cable, if they are important to sounding a fire alarm?

Mostly just thinking out loud.
 
18/4 for smokes? No 22/4 fire-rated cable available?

Do hardwired LV smoke detectors possess alarms, or does the control panel signal the horn to alarm? Or both?

Should the sounder output(s), and telco, be connected with fire-rated cable, if they are important to sounding a fire alarm?

Mostly just thinking out loud.
This has been discussed in this forum before....but here we go again.......

The NEC requires type FPL (what you are calling fire rated, or some call fire wire) for smoke detectors. The NEC does not specify a size or color requirement. However, many local jurisdictions require a red jacket and some require size #16AWG. That is why you a lot of FPL in the color red of that size. However, as I mentioned before, the NEC doesn't require this.

Plus another interesting fact is that the NEC allows type CM cable as a substitute for type FPL. CM is regular telephone wire. Most CM is also rated CL2 which is regular burglar alarm wire. So that means that the NEC allows the use of regular burglar alarm wire for smokes (as long as the cable is type CM, which most are).

Now for the other components of the system..... some jurisdictions say that if you have smoke detectors, then everything in the system must be rated FPL. This would include the keypads, power supply, siren, and smokes. This issue seems to be controversial as the NEC language is not very clear on this . However, as I mentioned above, the NEC only requires type CM.

Local requirements vary from the NEC when is come to smoke detector wiring requirements. It is best to consult with your local fire marshall or electrical inspector to find out what your local requirements are.
 
Somebody on here got themselves in trouble for using fire rated (or at least red) cable for purposes other than smoke/life safety and had to make a bunch of changes.

I would say only use fire rated for the life safety systems.

The LV company that pre-wired my house for alarm used 22/4 for everything. Since it doesnt move much personally i think solid will be fine and it's easier to work with when terminating.

I have used some cat5 for motion sensors (would have used 22/4 but i didnt' have it at the time), the current is so small i don't see it being an issue, but the little wires are a pain to work with as already mentioned.
 
Thanks guys. I haven't researched smoke alarms yet - I really appreciate the info. Seems like FPL 18/4 would be the best option for most smoke alarms - at least one will be wireless.

Smokes will be part of Phase II of my install, after the M1 is up and running.

I have hardwired smokes already (110v), so I'm basically supplementing them with a few additional.

(Wiring the HV smokes into the alarm will be part of Phase IX, if I live that long. :) I've read a few of those threads.)
 
Thanks guys. I haven't researched smoke alarms yet - I really appreciate the info. Seems like FPL 18/4 would be the best option for most smoke alarms........
While you are shopping, just be aware that there are several types of "fire wire". There is FPL, FPLR, and FPLP. All you need for residential is FPL, that is the standard fire-wire. You don't need the FPLR (riser rated) nor the FPLP (plenum rated). FPLR and FPLP are both much more expensive than standard FPL.
 
Sandpiper - do you ever use riser-rated cable? Since some of my hardwired smokes will be on other floors, I would think the FPLR might be appropriate for me. In reality, I'm sure the standard FPL would work just fine for me, extending through vertical conduit, but I'd hate to have to replace it if an inspector saw it.
 
Sandpiper - do you ever use riser-rated cable? Since some of my hardwired smokes will be on other floors, I would think the FPLR might be appropriate for me. In reality, I'm sure the standard FPL would work just fine for me, extending through vertical conduit, but I'd hate to have to replace it if an inspector saw it.
The NEC is clear on this. In section 760.154(B), the NEC lists the conditions when riser cable is required, basically in vertical runs between floors. However, section 760.154(B)(3) states this: "Type FPL cable shall be permitted in one- and two-family dwellings."
 
Thanks so much, Sandpiper. You just saved me a bundle.

Does that apply to all cables? I don't have a copy of the NEC, at home ('pirate' draft soft copy of the NEC on work PC, that I found online).
 
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