Infrared ray barrier composed of a transmitter module and a receiver module. It is a reliable outdoor and indoor detection system. Ideal for perimeter protection of farms, fences, houses, entrances, etc. The modules can be installed outdoors and have an anti-sabotage tamper, which triggers the alarm if someone tries to tamper with them. The alarm signal is activated when someone passes through more than one infrared beam simultaneously; that is, it avoids small animals such as pigeons, cats or other animals weighing less than 12 kg.