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One effective solution to prevent speeding in com-
mercial vehicles is to equip them with a road speed lim-
iter system, which restricts maximum road speed to
the required speed limit without loss of engine power.
This is realized by limiting the required fuel demand ac-
cording to a set speed limit. The maximum speed
limit is set using an electronic control unit.
Information about the current speed of the vehicle is
measured with a speed sensor that supplies an elec-
tronic speed signal to the control unit. The control unit
limits the fuel output in different ways, depending on
the fuel injection technology of the engine. In addition
to its main function, limiting the maximum speed, the
system offers a variable speed limiter as an option. The
driver can activate this feature below the maximum
speed limit in areas with lower speed limits.
Furthermore, the speed limiter includes additional
speed limit inputs to preprogram smaller speed limits
than the maxi mum speed. This functionality can be
used to prevent fast driving if any special function in
the vehicle is activated (like open doors on a city
bus or people on the platform in the back of a garbage
truck).
