How the O3 Senses Light Level

How It Works

The light sensor on the O3 measures illuminance, presented in either lux or foot-candles. Illuminance is the intensity of the light level at the point where the sensor is located (on the under-side of the device).

Wikipedia (Lux): "Illuminance is a measure of how much luminous flux is spread over a given area. One can think of luminous flux (measured in lumens) as a measure of the total "amount" of visible light present, and the illuminance as a measure of the intensity of illumination on a surface."

• Precision: 6 lx ±5% of reading
• Range: 10 lx to 5000 lx
• Viewing angle: > 90 degree (at 50% sensitivity)

Frequently Asked Questions

What is the physical range or radius from which the sensor can detect light?

This kind of question cannot be answered, because the sensor only measures illuminance (the light intensity on its surface), and not the luminous power/energy of a light source. Therefore, distance is not a relevant variable for the sensor, just the light intensity where the O3 is located.

Can the O3 be mounted above light fixtures in a room?

There is no definitive answer to this, because it depends on how intense the resulting illuminance is where the O3 is located. If you have a constant light source, that will create a 'base' light level that you would have to account for. So it depends if the base light level is so bright that any changes to light energy elsewhere in the room cannot be detected.