flickermeters

A flickermeter is a device used to measure electrical flicker in power systems, specifically the perceptible fluctuation in light output caused by voltage variations, lamp ballast electronics, or dimming devices. It is used to quantify flicker severity and to assess compliance with lighting and power-quality requirements.

Most flickermeters include a light sensor (photodetector) to monitor luminaire output, a signal conditioning stage, and digital processing that analyzes the signal to estimate human-perceived flicker. They convert optical fluctuations into an electrical signal and compute flicker indices such as short-term flicker severity Pst and long-term flicker severity Plt, following standardized methods.

The primary standards are IEC 61000-4-15 Flicker measurement and related methods, which define the measurement procedure, time windows, weighting, and the calculation of Pst and Plt. National or regional standards may also specify limits for voltage fluctuations and flicker in public networks (for example EN 50160).

Flickermeters are used by electric utilities, lamp and ballast manufacturers, energy auditors, and researchers to evaluate lighting quality, perform grid impact studies, and verify product compliance with flicker limits.

There are basic meters focused on Pst/Plt computation and more advanced instruments integrated into power-quality analyzers with additional metrology such as spectral photometry, color rendering, or chromatic response. Accuracy depends on sensor characteristics, dynamic range, sampling rate, and calibration against a reference photometric standard.

Limitations include dependence on luminaire type and viewing geometry, ambient light, and sensor response; flicker measurements should be interpreted with knowledge of the specific test setup and defined time windows.