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CEM3 User Manual
Square Law (Square)
At low control levels, much of a traditional incandescent fixture’s light output is in the invisible infrared
spectrum. This results in poor visible response to low control levels. A square law curve applies a
multiple derived from the square root of the control level (with full output equal to 1.00) to increase
voltage response at low control levels to compensate for the infrared loss.
Modified Square Law (Mod-Square)
A standard square law curve may overcompensate for infrared loss, resulting in “steppy” response to
incremental control changes at low levels. The ETC modified square law curve applies a second
multiple to the standard square law curve for more uniform response to control levels changes across
the entire range of dimmer output.
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