EMS Group will be using International Firex 2009 to unveil a new generation of wireless analogue addressable fire detection systems that use new radio technology.
The FireCell system incorporating Smart Cluster Technology (SCT) makes the product fully conform to the latest EN54 part 25 requirements. FireCell uses the European-wide 868Mhz frequency band and new bi-directional multi-frequency communication techniques. SCT is a cluster radio network that provides a number of advantages the makers say over traditional wireless fire systems. The fire alarm control panel connects to a multiple frequency Radio Hub that co-ordinates the wireless communication with up to 64 radio clusters. Each cluster can contain up to 32 wire-free smoke detectors, sounders, call points and I/O devices. The control panel can monitor a maximum of 512 devices throughout a building without using expensive fire-rated cable.
The radio devices in each cluster are monitored by a Radio Cluster Communicator (RCC) that also serves as a bi-directional range extender, passing the communications to and from the Radio Hub to the more distant areas, this enables according to the product firm complete building coverage. The RCC does not require a wired link to the control panel. In the unlikely event of a RCC failing, other RCC’s take over the reporting path and maintain communication with the Radio Hub. This arrangement provides a fault-tolerant solution, giving it is claimed flexibility for the designer and installer. The advanced secure bi-directional communications ensures that even when passing up to four RCC’s, a signal from any device can reach the control panel in 0.5 seconds.
The system’s radio coverage far exceeds the range achieved by other 868Mhz based wireless fire systems, EMS say. This is achieved by the use of diversity reception, multi-path techniques and the use of multiple frequencies. FireCell’s immunity to radio interference is also minimised by the ability to automatically change operating frequency channels. FireCell can use compatible analogue addressable fire sensors from either GE/Ziton or Apollo. The fire sensors attach to radio bases that are completely self-contained and internally powered using a dual supply from low-cost alkaline batteries. When the batteries are approaching the end of their useful life, warning is given to allow the replacement of the batteries within a reasonable timescale.
The operation and capability of FireCell’s control panel with cause-and-effect functions will be familiar to anyone who uses conventional multi-loop analogue addressable systems, the makers add. This allows the engineers’ current experience with traditional systems to be used as the basis for programming the FireCell wireless system. All the clusters of devices can be logged onto the system via the Radio Hub. An automatic configuration process then allocates the most appropriate frequency channels for the location and tests the integrity of the radio network. Cabling faults often found during commissioning of hard-wired fire systems are eliminated. During the life of the system, buildings may be refurbished or changes made and devices can be repositioned moving from cluster to cluster to suit the new requirements.
