The VTB EN54 Part 3 and 23 Approved sounder beacon is part of the VTG / VTB family of products designed for use with conventional fire alarm systems. The sounder function like all VTG family of products comes as standard with 32 tones. The VAD beacon has been approved to EN54-23, at W-2.4-7 coverage range (reduced room size coverage available via the DIL switch W-2.4-4, but does not comply with EN54-23). The sounder function features a 2-stage alarm override which is activated by a third negative wire from the fire panel. Both the sounder and beacon functions are fully synchronised. The sounder function has been fully approved to EN54 Part 3 by Intertek on tones 1, 8, 11, 25 and 27. The product can also be used as a beacon only which is easily selected by a DIL switch at the time of installation. Approved at 1 Hz flash rate (0.5 Hz flash rate available via the DIL switch, but does not comply with EN54-23).