The Effects of Falling and Rising Edge Dimming on Static Energy Meter Errors

For a better understanding on what is causing static energy meter misreadings different current waveforms with falling and rising edges have been compared. Falling edge dimming showed higher static energy meter deviations due to the larger rate of change in the current, $\vert \mathrm{d}I / \mathrm{d}t\vert$, compared to the rising edge dimming. The difference in $\vert dI / dt\vert$ is due to the asymmetry inherent in the semiconductors used. No specific difference in static energy meter deviation was found due to the polarity of the $\mathrm{d}I / \mathrm{d}t$. Faling edges in the first quarter of the sine wave resulted in an overestimation of the consumed power just as rising edges in the second quarter. Rising edges in the first quarter and falling edges in the second however showed an underestimation of the consumed power. The underestimation seems to compensate the overestimation when using complementary waveforms.