Extension of the IEN traceability for AC voltages below 200 mV

This paper describes the system, the standards, and the procedures developed at the Istituto Elettrotecnico Nazionale Galileo Ferraris for the extension of traceability to low voltage ranges down to 1 mV. Specific new features are the technique for the generation of low voltage, the procedures for building the traceability down to 1 mV, and the method for the evaluation of the load correction based on perturbations with known admittances.