I'm trying to trigger a motion sensor on a door (for fun and to learn more about these systems) using Arduino based electronics (ca 5V, ca 50mA). According to Wikipedia, these sensors (PIR sensors, passive infrared sensors) work at >8-14000nm wavelengths - can these be tripped using an Arduino as power supply - in theory / practice, or are there good reasons why this is a futile fun experiment to start with? I'm guessing a common infrared diode will not do the trick (ca 1000nm).
These devices are sensitive at about 1Hz, try a blinking incandescent lightbulb with a reflector behind it.
If it doesn't work it might be between zones: try relocating it left or right a bit.
A person has a thermal brightness of about 100W but the reflector should boost a 3W lamp enough that it can be seen by the sensor.