Abstract: A system is provided for weighing railroad cars coupled in motion by providing a first scale and a second scale located forward of the first scale. The railroad cars are moved over the first and second scales, the rear trucks of the railroad cars are weighed on the first scale and the weight is stored. While the rear truck of a railroad car under consideration is on the first scale, the front truck of the railroad car under consideration plus the rear truck of the just preceding railroad car are weighed on the second scale. The weights on the first and second scales are totaled and the stored weight of the rear truck of the just preceding railroad car is subtracted to obtain the full draft weight of the railroad car under consideration.The railroad car under consideration may be loaded while it is being weighed and in motion.

Abstract: In electronic measuring systems the accuracy of measurement is affected by drift not only of the zero but of the gain due to temperature changes, aging and supply conditions. The invention provides an automatic gain correction means so as to maintain an accurate relationship between the magnitude of the characteristic being measured and the value displayed or recorded. The measuring system is such that a train of pulses is counted over a predetermined time interval with a train of pulses representing, by its pulse repetition rate, the magnitude of the characteristic. A reference count is provided and means are provided for generating a pulse train simulating a predetermined magnitude of the characteristic being measured. Means are provided for counting the pulses of the generated pulse train and means are provided for comparing the reference count with the count of the generated pulse train to determine any error in the gain.

Abstract: A weighing system is described in which a weighing platform is operatively coupled to a transducer arrangement included in an electrical bridge circuit having connected therein a tare resistor arrangement for balancing out the tare weight of the platform. Means are provided for selectively isolating the effect of the tare resistor arrangement from the bridge circuit so that the system output indicates the sum of the tare weight of the platform and the weight of any load on the platform, thereby enabling the weighing system to be checked using the weight of the platform.