Fire alarm and detection systems They are automatic and manual control systems that consist of complex and constantly innovating technology; whose purpose is to guarantee a prompt evacuation of the occupants of a building. Due to their great importance, these systems must be appropriately designed, installed, tested and inspected according to applicable codes and standards for specific projects.
Its main mission is to detect a fire outbreak at an earlier stage to alert and provide information to all occupants of the protected place, as well as to the people responding to the emergency.
This control system is composed of initiating, supervisory and alarm indicator devices that are distributed in the building according to standards and/or manufacturer's recommendations. These devices monitor the physical integrity of the system and announce the status of fire alarms and initiate the response to these signals. When an alarm generated by an initiating device occurs, the alarm control panel will visually and audibly present the alarm indicative signal.
These peripheral devices communicate with the alarm control panel through the following circuits:
SLC – Signaling line circuits.
IDC – Initiating device circuits.
NAC – Notification Circuits (Notification appliance circuits).
These devices will be powered from the alarm control panel and will be under constant supervision, in such a way that any circuit breakdown will trigger a signal on the central control board, indicating a breakdown in the system.
Applicable Standards
Data Sheeds 5-40 – Fire Alarm Systems
Data Sheeds 5-48 – Automatic Fire Detection
NFPA 72 – National Fire Alarm and Signal Coding
Components of a fire alarm and detection system
Alarm control panel
The addressed fire alarm control panel serves to program the sequence of operation of the various devices and equipment that are connected to the system. This control panel supervises the devices distributed in the field such as detectors, modules, alarm stations, among others.
The control board is capable of identifying and reporting failures of all peripheral elements associated or connected to it, such as: discharged batteries, detector failure, control loop cutoff, among others. It has devices that allow historical information of the data collected and the events that occurred to be saved.
Remote Announcers
Remote signal annunciation allows you to receive critical signals and control the basic functions of the system in a more comfortable and accessible place, without having to go to the place where the alarm control panel is installed.
Remote power supply
Remote power supplies supply voltage to notification devices located away from the fire control panel
The power sources, in turn, are monitored by the alarm panel, which, in the event of any damage or failure, will send a failure message to the fire alarm panel through the monitoring module.
The external power supply kit is designed as a universal power supply and has space for two 12 V/7.2 Ah batteries.
Initiating devices
Manual alarm stations
A manual station is an element used to manually generate the fire alarm signal and send this to the alarm control panel to generate the respective outputs.
A manual station in its simplest form, the user activates the alarm by pushing and pulling down on the lever, which completes the circuit and locks the lever in the activated position for sending a signal to the fire alarm control panel. The word “activated” appears after the lever is pulled down.
Heat detectors
Linear cable detector
A linear cable detector is a special cable consisting of extremely low resistance twisted pair and trimetallic conductors coated by advanced thermal polymers. These polymers have been chemically developed to break down at a fixed temperature allowing the stranded conductors to make contact and initiate an alarm signal.
Fixed temperature detector
A fixed temperature detector is an electronic device that, through the principle of heating a thermistor, activates an alarm when the temperature of the air around it reaches a temperature limit set by the sensor.
Thermovelocimetric heat detector
A thermovelocimetric heat detector is an electronic device designed to activate an alarm when it detects a rapid increase in the temperature of the surrounding air, around 8°C per minute, regardless of the initial temperature.
spark detector
A spark detector is an electronic device that is designed to detect hot particles, sparks and flames within a process that could become an ignition source of a fire or explosion if they were allowed to circulate through the ducts to other equipment. of materials handling. Once the particle is detected, it must be automatically extinguished within milliseconds before it can create a fire or explosion.
Flame detector
A flame detector is an electronic device used when there is a risk of smokeless combustion, for example when combustible gases or liquids are present. Flames emit electromagnetic radiation in the infrared (IR), visible light and ultraviolet (UV) wavelengths which the detector is capable of detecting and sending an alarm.
Gas detector
A gas detector is an electronic device that uses the principle of sampling and analyzing gas concentrations in its catalytic sensor. It is activated when the sensor begins to perceive dangerous high concentrations of gas in the environment in which the detector is located. This type of device is used to detect leaks or other emissions (combustible, flammable and toxic gases).
Smoke detectors
Aspirating smoke detector
An aspiration smoke detector is an ACTIVE electronic smoke detection device, that is, it does not wait for the smoke to reach the device to activate the alarm, but is permanently “sniffing” the environment in search of smoke.
This works by constantly sucking air into a network of pipes distributed through a very effective vacuum cleaner. The air sample then passes through a two-stage filter.
The first stage removes dust and dirt from the air sample before entering the laser detection chamber. The ultra-fine second stage supplies additional clean air to keep the detector's optical surfaces free of contamination, ensuring stable calibration and long detector life, as well as minimizing nuisance alarms.
From the filter, the air sample flows through the calibrated detection chamber where it is exposed to a laser light source. When there is smoke, light is scattered in the detection chamber and the highly sensitive receiving system instantly identifies it. The signal is then processed and presented via bar graph displays, alarm threshold indicators or graph display.
Spot smoke detector
A smoke detector is an electronic device that, using the principle of light dispersion, detects the presence of smoke in the air and emits a signal notifying of the danger of a fire outbreak.
Beam type smoke detector
A beam-type smoke detector is an electronic device that has an emitting element and a receiving element, which, using the principle of a beam of light projected with ultraviolet (UV) and infrared (IR) pulses between the elements, detects smoke. It is activated when visible smoke obscures the beam of light rays projected by the emitter, reducing the light received at the receiver located at a distance.
Monitoring devices
Water flow detector
A water flow switch or detector is an electromechanical device designed to send an alarm to a fire alarm panel when a continuous flow of water occurs through the pipe of the automatic fire sprinkler system once the bulb is broken. of a sprinkler due to the increase in temperature caused by a fire.
Valve supervisor
A control valve switch or supervisor is an electromechanical device designed to send an alert signal to a fire alarm panel when an automatic fire sprinkler system valve is closed due to system maintenance or human error.Tank water level detector
A water level switch or detector is an electromechanical device designed to send an alert signal to a fire alarm panel when the water level in the fire tank decreases due to activation of the automatic fire sprinkler system or due to any leak in the tank.
Air pressure detector
A water level switch or detector is an electromechanical device designed to send an alert signal to a fire alarm panel when the water level in the fire tank decreases due to activation of the automatic fire sprinkler system or due to any leak in the tank.Notification devices
Sirens with strobe
These devices are used for the evacuation of personnel by means of an alarm tone, they are strategically placed in the areas where the greatest concentration of individuals is found and thus initiate evacuation actions. It is a component of the system that provides audible and visual output, with selectable output voltages 12 or 24 Volts, 88 decibels, with selectable output candles 15, 15/75, 30, 75, 95, 110, 115.
