- Reaction score
- 5,940
As far as I understand it, a PIR sensor has a spread of sections that are sensitive to heat, generally approximately human body temperature, though any wide range of heat source will work and the received light is focused onto the section.
Each section is looking for a change in heat reception, i.e. a presence or absence of heat, if this change occurs from one section to another, or repeatedly on one section, depending on the algorithm used by the manufacturer, then the PIR will trigger an output.
A moving incandescent lamp should trigger a PIR as it will be sending out a wide range of IR wavelengths, similarly if the lamp is switched on the detecting section will register a change in temperature as the lamp heats up from cold and as it passes the temperature range and so will also trigger.
Each section is looking for a change in heat reception, i.e. a presence or absence of heat, if this change occurs from one section to another, or repeatedly on one section, depending on the algorithm used by the manufacturer, then the PIR will trigger an output.
A moving incandescent lamp should trigger a PIR as it will be sending out a wide range of IR wavelengths, similarly if the lamp is switched on the detecting section will register a change in temperature as the lamp heats up from cold and as it passes the temperature range and so will also trigger.