Bidirectional magnetic flowmeter

In a magnetic flowmeter comprising a body adapted to be connected in a flow system for measuring the flow of a fluid therethrough, means for generating a magnetic field in said fluid flowing through said body, a pair of electrodes in said body for sensing a voltage generated in said fluid, and signal processing means for producing an output signal dependent on the magnitude and polartiy of said voltage, said signal processing means comprising differential amplifier means for producing a flow-dependent signal dependent upon said voltage, said differential amplifier means including an output and a pair of inputs, each of said inputs being operatively connected to a respective one of said electrodes, and amplifier means for amplifying said flow-dependent signal, the improvement wherein said signal processing means include polarity-sensing means for sensing a change in the direction of flow through said body, and flip-flop means for reversing the connections between said electrodes and said inputs of said differential amplifier means in response to a change of said direction.