While the range of a Honeywell motion detector will vary depending on the model number of your particular device, the majority of Honeywell motion sensors will be able to detect motion up to thirty five feet from the installation location of the motion sensor. Most Honeywell motion detectors work on passive infrared (PIR) technology. PIR motion detectors utilize various detection zones that are all designed to protect different areas of the protected room. You may have some detection zones designed to protect the area seven to ten feet in front of the motion. You would then have another set of detection zones that shoot out and protect the area from ten to 20 feet from the motion. Finally, you would have a set of long range detection zones that protect from twenty to thirty five feet from the motion. Each group of detection zones is made up of many different "fingers". The fingers are spread out over a ninety degree angle starting from the actual motion sensor. You can see in the picture below the detection zones and fingers for a 5800PIR-RES wireless motion detector. The top view shows how the fingers fan out from the motion to create a cone of detection. The side view shows where the three different detection zones actually hit on the floor. It is important to note that all ranges listed for a Honeywell motion detector are based on the intended mounting height. If you were to mount the sensor lower or higher, the detection zones would fall in an entirely different location. Therefore, it is strongly recommended that you follow the installation guide for your particular motion detector to ensure that it is mounted at the designed height. If you choose to mount it at a different location, you will need to do a thorough walk test of the motion area to determine where exactly motion would be detected. Of course, we always recommend that you walk test your motion detector to ensure that your chosen installation location will adequately cover the room you have your motion detector installed in. If you need instructions on how to walk test your Honeywell motion detector check out the following video: