New low-cost single-beam light barriers are now available from Pilz Automation Technology with either an infrared beam or, if faster response or a longer sensing range is necessary, a laser beam. For applications requiring body detection, the single-beam light barriers are considerably more cost-effective than safety light curtains. Indeed, Pilz says it costs less to purchase three single-beam sensors and one of its PNOZmulti modular safety controllers - giving enhanced diagnostics - than to buy a standard three-beam safety light curtain.
When used in conjunction with an approved evaluation device, the PSEN op2S-1-1 sensor can be used as a Type 2 optoelectronic protection device in accordance with EN IEC 61496-1 (Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements and tests) and EN IEC 61496-2 (Particular requirements for equipment using active opto-electronic protective devices (AOPDs)). Similarly, the PSEN op4S-1-1 and PSEN op4S-1-2 can be used as Type 4 protection devices. Sealing to IP67 makes the sensors suitable for use in the vast majority of industrial applications, including safeguarding of robots, palletisers, automated warehouses and transfer lines.
With their compact M18 threaded bodies, the sensors are quick and simple to install, and wiring is completed quickly and simply via M12 connectors on the transmitter and receiver. LEDs are incorporated within each unit to assist with commissioning and troubleshooting, but diagnostics are further improved when the sensors are connected to either a Pilz PNOZmulti safety controller or a Pilz PSS (programmable safety system).
The PSEN op2S-1-1 and PSEN op4S-1-1 infrared units have an LED source that provides a maximum operating range of 8m and a response time of 1.5ms, while the PSEN op4S-1-2 visible red laser version has an extended range of 40m and a response time of just 320us. If required, mirrors can be used to reflect the light beams so that access to hazardous areas from two or more directions can be protected.