Evolution and Types of Fire Alarm Systems

Fire alarm systems have been in existence since 1658, when men used to walk around the streets on the lookout for fires. They used to carry buckets on ladders and ring bells to warn the people about any fires. Electric alarms were invented in the late 1880’s and had a thermostat that detected heat and triggered the sprinkler system to douse the fire.

Fire alarms have come a long way since then. Today there are different kinds of fire alarms; however, all fire alarm systems essentially operate on the same principle. If a detector detects smoke or heat or a break-glass unit is operated, then an alarm is sounded to warn people about a fire. The fire alarm system may also include remote signal equipment that will alert a fire brigade. Typically, there are four categories of fire alarm systems. These include conventional, analogue addressable, addressable and wireless.

Conventional Fire Alarm System: Also known as four-wire fire alarm systems, these are used mostly in smaller properties. They are quite inexpensive when compared to other alarm systems. The conventional fire alarm system works by dividing the building into many detection zones. The detectors and call points within each zone are hardwired on dedicated, individual circuits to the control panel.  There may be many detectors in a single zone. When a detector is activated, the circuit that contains the triggered device is identified by the control panel so you know which zone the fire alarm has originated from. The area is then manually searched to pinpoint the individual device that was triggered.

Two-Wire Fire Alarm System: These are also used by small operations. These alarm systems are also based on the conventional system technology. The difference is that in a two-wire system, the call points, detectors and alarm devices for each zone are wired on the same set of two core zone cables back to the control panel. This means that a single circuit is used for detection as well as to power the sirens for each zone. Two-wire systems are more expensive than four-wire systems; however, they are more flexible, quicker and cheaper to install and also have additional features.

Addressable Systems: The system of detection followed by addressable systems is similar to a conventional system except that in this case the control panel can pinpoint exactly which detector or call point has raised the alarm. The detection circuit is wired as a loop and multiple devices can be connected to each loop. The detectors are basically conventional detectors with a built-in address.

Analog Addressable Fire Alarm Systems: Analog addressable fire alarm systems are often known as intelligent alarm systems that are used in large commercial properties and complex network systems. They are more expensive than conventional systems, but have greater flexibility, speed of identification and scope of control. Analog addressable fire alarm systems give details on individual detectors.

In these systems, different kinds of initiating devices are wired in one or more single loops around the sites. They require lesser cabling as compared to conventional systems and each detector or call point has its own unique address.  The fire control panel receives information for each device and you can pinpoint the exact location of the fire, smoke, fault, heat, etc.

Wireless Fire Alarm System: Wireless fire alarms are an effective alternative to traditional wired fire alarm systems and are useful where wired installations are not suitable. They use secure radio communications to interconnect the sensors and devices including smoke detectors, call points, etc. with the controllers. There are no cables between the detection devices and the control panel.

However, wireless alarm systems are slightly more expensive, but they are more flexible, easier and cheaper to install. Today, wireless systems have become increasingly reliable and hence are a popular option, especially for construction sites where they can be used on project after project without incurring purchase costs each time.

Today, Cygnus products are defining the way businesses ensure the safety of their employees as well as the workplace in the case of a fire. The top-quality Cygnus fire alarms systems go a long way in maintaining the best safety standards in the industry.