This is the X10 Powerhouse brand wireless supervised P.I.R. (passive infrared) motion sensor model number MS10A for use with any X10 wireless security system base receiver (PS561, SC1200, or DC821) or it can be added to any X10 wireless security system (DS7000, SC1200, DC8700, SS5400, SS5402). Also works with some Radio Shack wireless security systems. When motion is detected, the sensor sends an RF signal back to the security console setting off the alarm.
This sensor is first initialized into your security systems console so that it can be recognized. A random code is automatically generated during set-up, which uniquely identifies each sensor. The security console logs-in each of these random codes as the next zone in sequence (up to 16 zones). You can install as many security sensor types (MS10A motion or DS10A door/window sensors) as needed for a total of up to 16.
This sensor is self checked every 90 minutes for proper operation. If a sensor does not report in this could mean a weak or dead battery or that it has been tampered with. The security console will not arm if the motion sensor hasn't reported in, but this can be overridden by pressing the console's BYPASS button. It detects any movement within a distance of up to 40 feet at a 90 deg; field of view.
It has a sensitivity selector switch so the sensor can be set to trip the alarm if any movement is detected (most sensitive) or if two movements or continuous movement is detected (less sensitive). Note: The less sensitive setting doesn't make it pet immune. I've found the best way to get around false alarms from a pet is to put some white vinyl tape across the bottom of the "eye" to raise its field of "vision" above the height of your dog or cat. You will need to tinker with this to get the right amount of coverage to match your area being protected and your pet.
Class of X10 home automation device: Security Motion Sensor