You may not need to design or install a fire alarm system yourself but it never hurts to know about the fundamentals of something that is a vital part of your building. If you know how to disarm the control panel of a system gone berserk, troubleshoot the heads, pull stations, horns, and zone wiring so that the equipment is up and running again you might be able to restore fire protection for the building by yourself. These problems of fire alarms are quite common. So if you are thinking of getting into the profession of fire alarm installation, then it is important to know the basics of fire alarms, their common issues and solutions.
Modern fire alarm systems can detect smoke and heat from a small fire. They are capable of water flow through a sprinkler system or an activated pull station. They can send signals to security personnel about the fire through a dedicated phone line. Fire alarm systems have an addressable head. This head identifies the exact location of the fire. The head has enhanced diagnostic capabilities. To add a location for monitoring, an installer must put in new heads, pull some extra wires and insert printed circuit boards into the control panel. The heads possesses an address which conveys its location.
A fire alarm system has the following components
Initiating device that puts the system into alarm state. These can be photoelectric smoke and heat detectors, ionization smoke detectors, heat detectors, in-duct smoke detectors, manually operated pull stations and sprinkler waterflow sensors.
Indicating device that announces that there is a fire to the building inmates as well as security personnel in remote locations. These can be sirens, horns, strobe lights, chimes, bells or combination units. Indicating devices also come in weatherproof versions.
A control panel containing programming and operating electronics. This contains replaceable circuit cards for each zone or head. The control panel also consists of an alphanumeric display which shows the state of the system(normal or alarming state) and a touchpad so that operating personnel can reset the system after an alarm is triggered to restore the system back to normalcy.
Sealed batteries that are usually of 6V wired in series to make a 24 VDC power limited system. The batteries can be housed in the control or in a separate space. They are shipped with a charger which is connected to the AC power supply. When power fails, the system runs without interruption.
Auxiliary devices like LED annunciators that shows the state of the system as well as where an incident of fire has taken place.
Installation tips: During initial setup, all zone wiring, initiating device and indicating device installation should be completed before the telephone tie is hooked up. This is so that the monitoring agency doesn’t receive a false alarm.
The control panel should be located where one could respond to its alarms around the clock and also be able to rush to the building from there to verify the fire in the building before restoring the alarm. This place can be the building security headquarters, in the maintenance office or near a telephone switchboard.