1. A weighing apparatus for measuring a load weight, the apparatus comprising: a plurality of load sensing transducers each producing an output; a means for providing an electrical sum signal representing an approximate sum of the plural load sensing transducer outputs, a switching means having inputs connected to receive at least the sensing transducer output signals and an electrical sum signal, said switching means for selecting a predetermined sequence of said inputs of said switching means; a converting means coupled to the switching means for converting said predetermined sequence to a digital representation; and a processing means coupled to the converting means for processing the digital representation to derive a weight measurement result wherein the processing means uses the digital representation of the approximate sum signal together with the digital representations of the individual transducer signals to derive the weight measurement result.