Fire alarm system?

Question

In a fire alarm system would each break glass call popint be wired individually back to the control panel or would they be wired in series? What way would Smoke detectors be incorporated into the system and bells. I have 3 smoke detectors in the building and also a heat detector and carbon monoxide detector in the kitchen all interconnected and mains operated.

Would it be best practice or a regulation law to have these changed and incorporated into the control panel and if so would i have to change the wiring so they recieve their supply from the control panel?

Sorry if this is confusing i have worded it the best I can!

Cheers

Answer 1

Well, since I don't know where you are and what the building's use is, it's hard to say what's law or code and what isn't, so let's take the approach of "best practice".

First, lets talk about the pull stations. If you have a conventional zoned system there are two ways you can wire the pull stations. You can wire them individually, which each on a dedicated zone, so you know which one has been pulled simply by looking at the zone label. If they serve different floors, then they should be wired in this fashion. If your building is all one floor, then you can also wire them in series with usually a end-of-line device, like a resistor, at the last device. However, when they are wired in this fashion you will not be able to tell which one was pulled from the panel on a conventional system.

If your system is addressable (meaning there is a unique address that is set at each pull station), then they are essentially wired in series and the main panel will still be able to tell which one was pulled because each station reports on its own unique ID. (However, if your system is small, which it sounds like it is, chances are it's not addressable.)

Smoke detectors wired to the mains and interconnected are fine if they are permissible by local code. You may want to consider connecting them to your fire panel so the fire panel is activated when the detectors go off. If your panel is equipped with batteries so it can function if you lose main power, then it may be worthwhile to consider changing to a detector that can be powered directly from the control panel so you still have protection, even if the mains fail.

Carbon monoxide detectors are generally not connected to the fire alarm, but certainly can be if you want. I don't think the code requires them to be connected, but again, that can differ depending on where you are.

You mentioned a kitchen. If your kitchen is equipped with a commerical suppression system in the hood, be sure to connect the suppression system to the fire alarm.

That's about all I can say without knowing more specifics about your application.

Answer 2

most modern fire alarm panels use addressable systems where each detector/break glass etc. is given a unique address.They can all be wired in parallel, and a resistor is fitted across the last detector. The sounder/bell circuit is wired separately and must be in a fireproof cable such as MICC[pyro] or Firetuff. I dont think the carbon monoxide detctor would go onto this sort of system I cant think of one that would support one

Answer 3

It sounds as if you have what are called smoke alarms in industry terms, rather than smoke detectors. A basic difference is that smoke alarms are battery or AC powered. Some AC powered ones have batteries as a secondary supply, and/or to monitor the presence of AC. Most new ones can be interconnected so operation of one sounds all.

Smoke detectors are DC powered from a fire alarm control unit.

Smoke detectors can be simple switches, or sophisticated devices that can identify location as well as event. The same is true for heat detectors and manual fire alarm boxes.

Your CO detector may be either a stand alone unit, or possibly can be interconnected with your smoke alarms.

If you end up buying smoke alarms or smoke detectors, please chose those of the photoelectric type. They are much much better than ionization types for residential fires.

Answer 4

All I know is that different countries have different regulations in this area plus it depends whether your building is private or public. You must ask a proper electrician about this for safety's sake.