Final answer:
PIR motion sensors are most effective when mounted in areas with a clear line of sight to the monitored area. Mounting height and angle also play a role in their effectiveness.
Step-by-step explanation:
PIR motion sensors are most effective when mounted in areas where they have a clear line of sight to the areas they need to monitor. This is because PIR sensors work by detecting changes in the infrared radiation emitted by objects. If there are obstacles blocking the sensor's view, it may not be able to accurately detect motion.
For example, if a PIR sensor is mounted behind a thick curtain or wall, it may struggle to detect movement in the room on the other side. On the other hand, if the sensor is mounted in an open space with no obstructions, it will have a better chance of picking up motion in the area.
Additionally, the height and angle of the PIR sensor can also affect its effectiveness. For optimal performance, it is recommended to mount the sensor at a height of around 6-8 feet above the ground and angle it downwards slightly. This helps ensure that the sensor covers the desired area and reduces the chances of false alarms caused by motion outside of the monitored zone.