This International Standard applies to transducers with electrical inputs and outputs for making measurements of a.c. or d.c. electrical quantities. The output signal may be in the form of an analogue direct current, an analogue direct voltage or in digital form. In this case, that part of the transducer utilized for communication purposes will need to be compatible with the external system. This standard applies to measuring transducers used for converting electrical quantities such as the following: current, voltage, active power, reactive power, power factor, phase angle, frequency, harmonics or total harmonic distortion, apparent power to an output signal. This standard is not applicable for: instrument transformers that comply with IEC 60044 series; transmitters for use in industrial process applications that comply with the IEC 60770 series; performance measuring and monitoring devices (PMD) that comply with IEC 61557-12. Within the measuring range, the output signal is a function of the measurand. An auxiliary supply may be needed. This standard applies: if the nominal frequency of the input(s) lies between 0 Hz and 1 500 Hz; if a measuring transducer is part of a system for the measurement of a non-electrical quantity, this standard may be applied to the electrical measuring transducer, if it otherwise falls within the scope of this standard; to transducers for use in a variety of applications such as telemetry and process control and in one of a number of defined environments. This International Standard is intended: to specify the terminology and definitions relating to transducers whose main application is in industry; to unify the test methods used in evaluating transducer performance; to specify accuracy limits and output values for transducers.