wired zone, wired detector and wiring

Business security, commercial security, hotel security, factory security, industry security solution.
Posts: 832
Joined: Wed Dec 05, 2018 12:27 am

wired zone, wired detector and wiring

Unread post by vedard »

Wired alarm host or hybrid alarm host has wired zones. On the mainboard of the alarm host, we can see the terminals such as Z1, COM, Z2, Z3, Z4.....That is the wired zones.
There are two ways for wiring of wired detector and wired zone. That is N/C, It's short for Normal closed. It means the circuit is normal closed and when alarm triggers, the circuit changes to open circuit. Another one is N/O, it's short for Normal Open. It means the circuit is normal open and when alarm triggers, the circuit changes to closed circuit.
How to choose N/O or N/C wiring way?
To avoid the thieves to cut the wire without alarm, N/C wiring is always used for burglar alarm zone of PIR detector, microwave detector, motion sensor, door contact switch.
And on the contrary, to avoid rats gnawed the wiring and caused the alarm, N/O wiring is always used for fire alarm and emergency alarm zones such as wiring of smoke detector, heat detector, emergency button.
Will N/C wiring circuit triggers alarm when someone short-circuit it? Will N/O wiring circuit triggers alarm when someone cut the circuit?
Yes, there is EOL resistor used to monitor the circuit. The EOL resistor value is 2.2K, 4.7K or any, depends on the alarm host. At proper working statues, the monitored resistance value of the circuit is the resistor value. At N/O circuit, if circuit opens, the resistance value is ∞, it reports alarm. If circuit closed, the resistance value is 0, it reports fault.
Likewise, for N/C wiring circuit, the circuit opens will report alarm and the circuit closes will report fault.
Low power of the detector will be reported as well.
To monitor for other vandalism, tamper-resistance wiring is used. And there is a wiring way called 2 EOL resistors.
wired detector wiring.jpg
wired detector wiring.jpg (47.91 KiB) Viewed 1712 times
Shop Focus brand wireless alarm, HB solar power alarm, HST fire alarm at https://www.vedardalarm.com
Posts: 1
Joined: Thu Mar 30, 2023 6:29 am

Re: wired zone, wired detector and wiring

Unread post by ameliasarah »

There are 2 ways of tamper-resistance wiring. One way is to connect the detector tamper terminal to the alarm host tamper zone. In this way, the ...Installation Wiring Diagram. TYPICAL WIRING DIAGRAM. Figure 1(a) shows the typical wiring diagram of the 2-wire multiple-station smoke/heat detector system.A. Wiring the zones. You can wire zones to supervise normally open devices, for example smoke detectors or heat detectors ...features for applications where detectors are connected to conventional 2-wire or 4-wire initiating device circuits. (IDCs). Each TrueAlarm detector has an ...Fire alarm cables are placed into three broad categories: plenum, non-plenum, and riser. Each of these corresponds to another standardized category, and these terms reflect where the fire alarm cable can be installed safely. Plenum cable, to be used in ducts or other enclosed air spaces, is called FPLP.If you buy an AC-powered smoke detector today, it will have three wires -- black, white and red. Black accepts 120 volts AC, white is neutral, and red is the intercommunication wire.
Post Reply