OPZ "Antishock" fire alarm sounder

Antishock OPZ sirens are recommended for use in fire warning systems in accordance with the Code of Regulations SP3.13130.2009. The main controlling element of the electrical circuit is a microprocessor, which, measuring the voltage supply of the siren, forms the most optimal sequence of pulses to pump power into the resonant circuit of the sound membrane. Such optimisation allows to maintain the same sound pressure level in a wide range of supply voltages (from 6 to 30 V), while the current consumption decreases with increasing supply voltage. The sound signal generated by the siren is tone-modulated with frequency deviation in the range from 2.5 to 3.5 kHz. Smooth increase in the volume of the sound signal is especially relevant if among those to be notified there are preschool and primary school age children, elderly people and those on whom the sudden activation of loud sound signals can have a strong frightening effect.