Traditionally, radio surveys for wireless fire alarms involve assessing the signal strength and determining the correct locations for equipment and devices to ensure full wireless coverage across a site. A thorough radio survey is critical for legacy wireless fire alarm systems, but innovative new wireless mesh technology is reducing the need to conduct a radio survey before installation.
So, what makes mesh technology different?
With legacy fire alarm wireless networks, each device communicates directly with a central access point or router. There is a single path of communication with no redundancy so it is critical they do not drop off the network as they will never rejoin. But, with a wireless mesh network, all of the devices can communicate with each other, which forms a decentralized and self-configuring network.
A wireless mesh network is also beneficial when it comes to scalability. It is easy with a mesh network to add more devices as the building grows or changes. As the network is self-forming and self-healing, if a new device is added to the system, it automatically configures but if a device fails or is removed from the network it can also reroute to ensure the network stays operational, robust and reliable. A wireless mesh network also has up to three times the range of a traditional wireless system making it ideal for a variety of applications. For instance, in unusual or separate buildings – check out our project at the Rural Life Living Museum to see how Cygnus SmartNet can be used across different buildings.
BS 5389 and radio surveys
It is virtually impossible to determine exactly how each device decides on the best path of communication with a mesh wireless system, which is why we recommend conducting a survey after installation.
Section 28 of the BS 5839 Standard states that a comprehensive survey should be completed on each project. However, there is an important note, which states where a comprehensive survey cannot be completed, e.g. a new build, the final installation can be used as a survey.
With a mesh system, the installer simply needs to download a statistics log once the install is completed and at the point of commissioning. This supplies a list of the RSSI value of every single device and provides installers with all the information they need to submit the documentation required.
The power of SmartNet
With the capability for 511 devices to operate on one wireless system, a SmartNet network is built on a combination of battery powered radio devices, operating on a self-forming, self-healing mesh network using the renowned patented Cygnus wireless mesh protocol across 10 frequency channels operating at 865-868 MHz.
A minimum of two communication paths to each wireless device and innovative channel-hopping technology makes the network extremely reliable, protecting against the risk of broken communication links, network redundancy, interference and false alarms.
In addition, SmartNet devices feature a long radio range, extending up to 350m (unobstructed), with the help of an omni-directional antenna for increased device performance. SmartNet enables installers to design 16, 32, 64, and 96 zone panel options with the possibility to network up to five panels together in a single system.
By eliminating the need for cabling during installation, a SmartNet system greatly reduces engineering time and the overall project cost. This enables faster and easier installation on new buildings, where project timescales are often extremely pressurised. It also opens up the retrofit opportunity since wireless installation minimises occupant disruption and reduces the cost of rewiring. The wireless mesh network system also requires no gateway expanders or loop-powered translating devices to speed up installation still further.
As a BS 5839 and EN 54 certified system, SmartNet eliminates the need for fire-resistant cabling, restrictions on device locations and multiple loops, which need to be protected against failure. SmartNet also offers superior safety as there is no requirement for cable damage mitigation, no combustible fixings, no possibility of inadequate wiring and no risk of circuit overloading or high circuit loads.
To become a Cygnus Certified Installer, installers need to attend training at the Cygnus Academy – for more details get in touch here.