Abstract: A system for controlling an electromechanical siren is disclosed. The system includes an electromechanical siren comprising a siren and an electric motor, an automatic operation switch, and one or more processors. When a user activates the automatic operation switch from an open position to a closed position, the one or more processors activate the electric motor such that the electric motor drives the siren of the electromechanical siren. The processors allow the electric motor to run for a first non-zero duration of time, and, while the automatic operation switch remains in the closed position, and after the expiration of the first non-zero duration of time, deactivate the electric motor such that the electric motor ceases to drive the siren of the electromechanical siren.

Abstract: A filter (100, 200) is provided especially for high aspect ratio particles in a conduit (102, 202) for a fuel injection system. The filter (100, 200) can be an edge filter (100) or a sack filter (200) with an annular gap (116, 212) between the filter section (106, 206) and the conduit wall sized smaller than previously known in order to filter high aspect ratio particles without significant changes in pressure drop. The edge filter (100) relates the gap (116) to grooves (118) in the filter section (106), and the sack filter (200) relates the gap (212) to the size of the holes (210) in the filter section (206).