Chapter 12

Flicker

Introduction

Flicker quantifies the luminance fluctuation of lamps caused by supply voltage variations. The algorithm behind the measurement meets EN61000-4-15 and is based on a perceptual model of the human eye / brain sensory system. The Analyzer converts duration and magnitude of voltage variations into an ‘annoyance factor’ caused by the resulting flicker of a 60 W lamp. A high flicker reading means that most people would find the luminance changes irritating. The voltage variation can be relatively small. The measurement is optimized to lamps powered by 120 V / 60 Hz or 230 V / 60 Hz. Flicker is characterized per phase by the parameters shown in a Meter screen. The related Trend screen shows the changes in all measuring values in the Meter screen.

Note

After you have switched to Flicker, a settling time of about 10 seconds will pass before the measurement is started. During this time the U (Unstable) symbol shows in the screen header. Moreover the timer counts down from – 10 seconds. Flicker measurement has no unstable period when used with a timed start.

Meter screen

To access the Flicker Meter screen:

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MENU

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Fluke 435 user manual Flicker, Introduction