Fort Smart Pet Friendly PIR Movement Sensor for the Smart Home Alarm System. This Pet Friendly PIR movement sensor has an 8m detection range in a 110 degree field of view, to identify intruders and sound the alarm in an instant. It also has the capability to detect and ignore the movement of pets up to 25kg to prevent false alarms when you are in bed or away from your home. Each sensor is battery powered (batteries included) meaning they can be placed in a room of your choice and away from an active power source.