What is a Wailing siren?
This is a special type of siren in which the sound output of siren increases and decreases in a pre-defined format. Wailing or Wailing means continuously changing sound notes. The most commonly used wailing siren is of 4 Second ON time & 4 seconds OFF time type. Such type of sound output is generated with the help of the Warbling Relay control unit. This circuit turns ON the siren for 4 seconds & turns the siren OFF for the next 4 seconds.
Standard Wail 600–1200 Hz @ 12 cycles/min
Where are wailing sirens used?
Such sirens are used for Evacuation & Emergency Alert situations.