The MCR-07 PIR motion sensor for installation in suspended ceilings is used for automatic control of lighting or any other electricity receiver. Its design is based on a state-of-the-art passive infrared sensor (PIR). The device detects motion in the monitored area within the radius of approx. 5 m, 360° around the sensor. In addition, it checks the ambient lighting intensity condition, making sure that the light is only activated when necessary. If the device detects motion and the lighting level is below the preset value, the sensor will turn on the light and start counting the preset time. After the preset amount of time (if no additional movement is detected while the timer is active), the motion sensor will switch off the light automatically. This way, the sensor ensures optimum control of energy flow, optimising costs of illuminating passageways, toilets, utility rooms, etc. The device design enables easy installation of the sensor directly in a suspended ceiling and plasterboard.