Inertia safety switch

INERTIA SAFETY SWITCH

The inertia switch has the task of interrupting the electrical supply for the electric fuel pump if the vehicle is subject to violent deceleration (an impact) to prevent the fuel from coming out and causing the vehicle to catch fire in case the fuel manifold or the supply pipe is damaged.

The switch consists of a steel ball in a conical shaped housing which is kept in position by the attraction force of a permanent magnet.

The ball can be released from the magnetic clip, due to the action of the acceleration from the inertia forces, and gradually come out of the conical housing with an upwards movement which depends on the angle of the cone.

There is a rapid release mechanism which forms a normally closed (NC) circuit. When it is struck by the ball, the mechanism changes position into a normally open (NA) circuit, thereby interrupting the electrical supply to the electricpump and causing it to cut out.

The calibration of the switch causes it to intervene at acceleration above 1.2 g (approx 11.7 m/s2, corresponding to an impact at a speed of around 25 kph).

To restore the connection to earth for the auxiliary electric pump, move the seat backwards and press the switch until the click is heard.

After even an apparently slight impact, if there is a smell of fuel or there are noticeable leaks from the fuel system, do not turn the switch back on, but search for the cause of the problem and eliminate it to avoid fire hazards.

If this is not the case and there are no leaks and the vehicle is ready to be driven again, press the button to reactivate the electric pump.