Tying In new FA Device To Extg. Circuit

[mstrlucky74]

Sorry guys use to mostly bidding new construction work. Afew questions as I’m not exactly sure what takes place when you tie in a new smoke detector to an existing 25k sq. ft office space.

I guess I would need to know for sure if it's a class A or EOL.
How would you tie it in to the existing loop? Would you pull back cable to an extg. initiating device then run new? Thanks.

 

[gadfly56]

Sorry guys use to mostly bidding new construction work. Afew questions as I’m not exactly sure what takes place when you tie in a new smoke detector to an existing 25k sq. ft office space.

I guess I would need to know for sure if it's a class A or EOL.
How would you tie it in to the existing loop? Would you pull back cable to an extg. initiating device then run new? Thanks.

Find the two devices closest to the new device location, A and B, say. Pull the wire back from B and if it's long enough, feed the new device, A'. Then run new cable from A' to B. That's the cleanest way to do it, assuming you have open access to all devices and the paths between them.

 

[GoldDigger]

Sorry guys use to mostly bidding new construction work. Afew questions as I’m not exactly sure what takes place when you tie in a new smoke detector to an existing 25k sq. ft office space.

I guess I would need to know for sure if it's a class A or EOL.
How would you tie it in to the existing loop? Would you pull back cable to an extg. initiating device then run new? Thanks.

If it is EOL type and the existing device that you tie in at is not the current EOL point, then the same process described above applies. Or you could run two wires (in separate raceway??) to the nearest existing device to loop out and back again.
If it is EOL type and you are trying to tie in at the current End Of Line, you can just extend from that device and move the EOL resistor.

 

[active1]

It really wouldn't matter if it was a type "A" or "B", conventional, addressable, or a combination.
Be sure you don't overload the annunciating circuit (horn, strobe, speakers).

gadfly56 explained it best.

 

[mstrlucky74]

Thanks.

 

[goldstar]

It really wouldn't matter if it was a type "A" or "B", conventional, addressable, or a combination.

Actually, it does matter. If it's an addressable smoke detector system you'll need access to the program to add it. Otherwise, it will just show up as an unidentified point or, if it had the same address as another it will show up as a duplicate.

 

[active1]

Actually, it does matter. If it's an addressable smoke detector system you'll need access to the program to add it. Otherwise, it will just show up as an unidentified point or, if it had the same address as another it will show up as a duplicate.

Ya, your right. I thought about that, but didn't want to get to detailed for here & estimating.
Was just referring to the wiring side of things. Because that's all I figured would be doing.
Then bring in the FA company to install, program, document, & test, as needed.

 

[MisterCMK]

You are better off contacting a low voltage/fire alarm company and talking to them about it.