Abstract: A regulated voltage supply (10) for delivering a substantially constant voltage to a load (12) having a regulator (24) for controlling a raw voltage supply (22) to deliver that constant potential, wherein the supply includes sense leads (28 and 30) between the load and the regulator for monitoring load voltage, provided with a sense current cancellation circuit (30) for nulling sense current and preventing it from flowing through the sense leads; in a preferred implementation, including voltage-to-current converters (42 and 44) bridging respectively the output terminals (14 and 16) and the sense terminals (32 and 34), it provides a cancellation current equal in magnitude and opposite in direction to the sense current.

Abstract: A stable voltage reference is connected to a two channel digital to analog converter connected to a range setting amplifier which provides the calibrator output. A microprocessor zeroes the calibrator by shorting the inputs of a zero amplifier to provide a reference zero towards which the calibrator is adjusted. It establishes the relative weighing of the two channels by adjusting one channel one increment up from zero and measuring the number of increments required by the other channel to return to zero. The microprocessor determines the gain change in the converter by establishing a bridge with known components and relating changes in the bridge voltage to the shift in gain.