Choosing the Right Networked Fire System

Today there are greater demands on fire systems than ever before. Many fire panels are powerful computers, working with intelligent detectors to report on changing conditions across the fire system, alerting people to emergencies by voice, light, and/or sound. They also control the release of suppressants, operate smoke control systems, link to graphical control systems, and integrate with third-party building management systems. This list is constantly growing, as well as the demand for fire panels to operate across larger, more complex sites.

By Vladimir Zrnic, Regional Sales Manager for Southern Europe, Advanced

Flexible system architecture

A networked fire alarm system communicates data between all panels/network nodes on a site, allowing for greater control over the fire safety of the whole building.

The network’s design should allow buildings to be protected by distributing fire panels across the site. Using a true peer-to-peer system, information from any input or output device can be sent over the network and displayed on any control panel, allowing the system to display details of all fires on any panel or repeater in the building.

The interconnection of fire alarm control panels over a proprietary network allows many panels, often in physically different locations, to communicate using a two-core cable (or fire-resistant two-core screened twisted pair cable depending on local legislation). Information from any one panel is available to any or all of the other panels in a network, distributing intelligence, reducing installation costs, and saving time on maintenance.

A looped system is recommended to ensure greater system security as it uses diverse cable routing techniques. Should a single fault occur, affecting communications, the system can still function and communicate to provide a coordinated response.

System speed

In large, complex sites, it is vital networked panels perform effectively. As the number of panels and input and output options on a network increase, some systems can slow down dramatically compromising safety and reliability.

Advanced’s peer-to-peer standard or fault-tolerant networks can be configured to allow the interconnection of up to 200 panels (nodes) in a fault-tolerant configuration. The maximum cable length between nodes is 1.5km, with a total loop length of 20km. The network can withstand a single fault between nodes without losing communications to any single panel by using a standard two-core, fire-resistant cable.

EN54-13 specifies maximum times for relaying fire alarm signals around the network. EN 54-13 (E) 4.3.2.1 states that “a fire alarm condition on Control and Indicating Equipment (CIE) shall be indicated on the main CIE within 20sec.” The typical delay on an Advanced Ad-NeT+ 50 panel network, for each panel to indicate a fire from any zone, is less than one second and 3.5 seconds for a full 200 panel system.

This is important, since what is the point of having an investigation delay set to 30 seconds if communication through the network takes a whole minute? Failure to acknowledge the alarm through the network and start an investigation will result in full evacuations on large complex sites, which is not what we want.

Scalability

A truly scalable fire network will allow different typologies suitable for sites of various sizes with vast cause-and-effect options, and intuitive, easy programming. As buildings are increasingly networked, fiber optic cable has become popular, allowing fire alarm networks to cover greater distances.

Fire systems need to work quickly and reliably, and process large numbers of changing signals in the event of a real fire. On larger sites, seconds count and fast systems are highly valuable in maximizing verification time, escape, and firefighting. Individually, many fire systems may appear to meet these challenges but in complex buildings with networked systems attaining adequate performance isn’t always achievable with inferior fire panels.

For further information on Advanced’s AxisGo email: vzrnic@advancedco.com or visit: https://uk.advancedco.com/