Patent ID: 6674384
Filing Date: 2004-01-06
Classification: G01D

Abstract:
A process for making secure a processing of an analog signal delivered by a sensor of resistive analog type in a safety device on a lifting apparatus, the sensor supplied electrically with DC supply voltages, the analog signal delivered by the sensor being converted into a digital signal in an analog/digital converter of given resolution, the process comprising:at a first instant, acquiring and storing a first digital signal corresponding to a first analog signal delivered by the sensor; then, inverting the supply voltages of the sensor; after the inversion, at a second instant, acquiring a second digital signal corresponding to a second analog signal delivered by the sensor; summing the first and second digital signals; comparing the sum of the first and second digital signals with the resolution of the converter; and if the sum is substantially equal to the resolution of the converter, enabling a control signal for operating an actuator of the lifting apparatus, corresponding to a control pre-set.