headlight sensor

A motorcycle headlamp modulator (or simply headlamp modulator) is an accessory device that oscillates the intensity of a motorcycle headlamp at 240 ±40 cycles per minute (~4 Hz) between approximately 20% and 100% of full intensity. The headlight operates at full intensity 50-70% of the time. United States and Canadian regulations require headlight modulators to include a light sensor that disables modulation when the ambient light level drops below a certain point. When this happens, the headlamps burn steadily.

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