Abstract: A 100% solid state, liquid level control circuit which utilizes printed board construction with integrated circuits to control duplex pumps. Mercury switches provide information to the solid state, non-inductive input interface circuitry which relays this information to logic control circuitry and an alternator. The logic control circuitry and an alternator forward the information to solid state, non-inductive output circuitry for powering pump starters. The alternator selectively alternates the sequencing of the pumps for controlling the lead pump. Current limiting devices, light emitting diodes and logic control circuitry are combined to provide operation of pump starters for controlling the liquid level in a wet well, reservoir, bilge of a vessel, or the like.