Currently, one of the most important parts of the cloud and computing platforms are the data centers, since they house the equipment where the applications and information processing are executed. The vitalkey areas of data centers are the equipment sites. In addition to the fact that access is controlled and restricted to these areas, continuous monitoring of the presence of people in these areas is critical. The data centers have closed circuit television systems that allow this activity to be carried out; however, these systems do not send alert messages that allow timely reaction to any threat from unauthorized persons who have accessed the equipment site. Similarly, presence detectors of different technologies are used, which present disadvantages compared to the system presented here. For these reasons, in this work a motion detection system was developed based on the processing of video images captured with a camera integrated into a Raspberry Pi 4 card and programmed with Python and OpenCV functions. When the system detects movement, it sends a WhatsApp alert message to a mobile phone. The tests carried out showed that the system is accurate to 98.08%.