Is your Conserv sensor picking up light data when you know the lights are off?
Our Conserv sensor is extremely sensitive to light, and is capable of picking up indirect light or reflected light in very low-light conditions. It might be coming from a doorway or even a tiny light from a fire alarm.
If your sensor picks up higher than normal light levels in a space where you know the lights should be off (more than 5-10 Lux), then you might just have areas where light may be leaking in. If the levels are very high (over 100 Lux), you might even find that someone left a light on!