Hi

Solar sensor light (also called solar security lights) work as follows:

- The solar lights normally have a  passive sensor that detects infrared energy (ie heat) called a PIR (passive infrared) detector.  This sensor is sensitive to the temperature of a person.

- Interestingly it is worthwhile to note that the light will be sensitive to motion, but not to a person who is standing still, because the sensor is looking for a change in the amount of infrared energy being detected.

- When the sensor detects infrared it will switch the light on for some predetermined amount of time eg 30 seconds.

- Many solar lights have two modes: mode 1 is dim ambient light; and mode 2 which is much brighter is turned on by the PIR sensor.

The motion sensor is the one that detects movement and will illuminate the fixtures when someone is near and dims when someone is gone. Meanwhile, the light sensor automatically lights at sunset and automatically turns off to charge at sunrise.