IEC TR 61547-1:2020 RLV contains both the official IEC International Standard and its Redline version. The Redline version is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition.

IEC TR 61547-1:2020 describes an objective light flickermeter, which can be applied for the following purposes:
- measuring the intrinsic performance of all lighting equipment without the application of voltage fluctuations in terms of illuminance flicker; during this measurement, the lighting equipment is supplied with a stable mains;
- testing the immunity performance of lighting equipment against (unintentional) voltage fluctuation disturbance on the AC mains in terms of illuminance flicker; during this test a set of defined voltage fluctuations are applied to the AC mains and the immunity of the lighting equipment to the disturbance is determined.
Apart from the above two purposes, the immunity performance of lighting equipment can also be tested against intentional voltage fluctuation on the AC mains arising for example from mains signalling. This is however not described in further detail in this document. This third edition cancels and replaces the second edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- the scope of this document has been clarified to make a distinction between flicker testing without voltage fluctuations to measure the intrinsic performance of lighting equipment and flicker testing in which a specific set of voltage fluctuations are applied in order to measure the immunity of the lighting equipment to voltage fluctuations present on the mains;
- the test procedure for flicker testing has been clarified.