2 wire fire alarm panels are essentially an evolution of conventional panels. The principal benefit over standard conventional systems is the flexibility to install sounders on the same cable as detectors & call points for each zone. This mean each zone will only require a single circuit holding all applicable devices. Some manufactures believe this saves approximately 40% on cabling.
2 wire (sometimes referred to as bi-wire or twin wire) systems in most other respects offer the same or at least very similar functionality to a conventional equivalent. Alarm indication is limited to only showing which zone contains the alarm and these systems are installed with a separate radial cable for each zone.
The flexibility to install sounders on the same circuit for each zone has led to a tendency for many installers to opt for detectors that include built-in sounders as standard. By doing so it becomes straightforward to achieve the required sound levels according to the BS5839 fire alarm standard. Installation is streamlined with fewer devices being required and in many cases installers charge per device so this drives down installation costs.
There are however several consideration to be made before opting for a 2 wire system. Unlike conventional systems there is no compatibility between the various 2 wire systems on the market. That means if you decide to install System A, you will need to purchase the panel and all associated devices to go with that particular system. Also larger cable may be required, you can install the conventional systems we supply using 2 core, 1mm cable however the 2 wire systems we supply need 2 core, 1.5mm cable which is more expensive.
There are several 2 wire fire systems on the market from which we have chosen to supply the Fike Twinflex (formerly Fike Twinflex) system. Twinflex panels are available in 2, 4 or 8 zones sizes (they start at 2 zones as BS5839 fire standard dictates that each system must have at least 2 sounders on separate circuits).
Fike have recently released the next generation of panels, Twinflex Pro, which try to further the gap between conventional and 2 wire systems. Advanced features including an LCD display, the ability to define a label for each zone (for instance “Ground Floor”), event history and day/night mode are all included.
If you need assistance choosing the right 2 wire fire alarm panel feel free to contact us on 01792 452 700.
