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What is Frequency?

In the context of lighting, frequency refers to the number of waves or cycles of electromagnetic radiation per second. Frequency is typically measured in Hertz, abbreviated as Hz.

Frequency and Flicker

Light flicker is the undesirable result of a lamp receiving a lower frequency of electricity than it needs to power the bulb. In the U.S., electricity is delivered through alternating current at a power line frequency of 60 hertz, which is too low for high-intensity light sources such as fluorescent tubes, HID bulbs, and LED grow lights. As a result, fluorescent and HID lamps must use external ballasts to accommodate for a higher frequency, and LED lights are designed with a built-in driver to accomplish the same.