Abstract: A parameter display and alarm installation for a motor-driven vehicle, comprises a revolution counter device, a speedometer device associated with a general mileage recorder and a trip recorder, said revolution counter and speedometer devices comprising each a signal generator associated with a rotating element of the vehicle, an electronic transfer device having a predetermined duration of its "open" condition and adapted to receive the signals emitted by the related signal generator and to transmit said signals to at least one decoding device which transforms said signals with a view to displaying the same in a digital form, said installation further comprising at least one alarm circuit associated with said revolution counter and speedometer devices and adapted to indicate by an acoustic and/or optical signal any condition wherein the rotational speed of the motor of the vehicle and/or the speed of the vehicle exceed a respective predetermined value; preferably the installation further comprises means for