2T22

History

The Federal Signal 3T22 was originally designed as the 2T22 in 1952 or 1954. The 2T22 has the same number of ports and cones as the 3T22. The 2T22 can produce two main signals (the other signals are rarely used), hence the name "2T22" (the 2 at front representing the 2 choppers, and the 22 representing the number of horns). The 2T22 has no solenoids, so it cannot perform a "hi-lo" signal. In 1955, Federal designed the 3T22, with its main differences from the 2T22 being its name and the addition of solenoids/dampers. The solenoids allow the 3T22 to perform the "hi-lo" signal, which is mainly used for fire calls. The 2T22 and 3T22 can both produce 113-116db (measured 100 feet away from the siren). There are four models of this type of siren: the 2T22 A and B and the 3T22 A and B. In the name 3T22, the 3 stands for its three main signals: attack (wail), alert (steady), and hi-lo, and the 22 again stands for the 22 cones/horns. The A or B determines whether the motor is three phase or single phase. A 3/2T22A is three phase, while a 3/2T22B is single phase. The siren was mainly used for air raid warnings during the Cold War era and weather warnings such as Tornados after the war. In the early 1990s, the siren's production was halted when it was replaced with the newer 2001-SRN and later the Eclipse 8, of which the 2001 can reach 126db, hence the name. Like many other older siren models, these sirens are becoming less common due to towns upgrading to more powerful sirens. Many sirens are refurbished by enthusiasts or installed for lower-income towns that need sirens.