IEC 60688:2012

Applies to transducers with electrical inputs and outputs for making measurements of a.c. electrical quantities with a nominal frequency between 5 Hz and 1 500 Hz. The output signal may be in the form of an analogue direct current or in digital form. Supersedes IEC 688-1 and IEC 688-2.

IEC 60688:2021 applies to transducers with electrical inputs and outputs for making measurements of AC or DC electrical quantities. The output signal can be in the form of an analogue direct current, an analog direct voltage or in digital form. This document applies to measuring transducers used for converting electrical quantities such as – current, – voltage, – active power, – reactive power, – power factor, – phase angle, – frequency, – harmonics or total harmonic distortion, and – apparent power to an output signal. This document is not applicable for – instrument transformers that complies with IEC 61869 (all parts), – transmitters for use in industrial process application that complies with IEC 60770 (all parts), and – performance measuring and monitoring devices (PMD) that comply with IEC 61557 12:2018. Within the measuring range, the output signal is a function of the measurand. An auxiliary supply can be needed. This document applies a) if the nominal frequency of the input(s) lies between 0 Hz and 1 500 Hz, b) to the electrical measuring transducer if it is part of a system for the measurement of a non-electrical quantity, and if it otherwise falls within the scope of this document, and c) 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 document 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, and – to specify accuracy limits and output values for transducers. IEC 60688:2021 cancels and replaces the third edition published in 2012. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) updating normative references; b) additional requirements for specific transducers used for LV monitoring applications; c) creation of interface coding to ease selection by the end-user.