IEC/EN 61496 – which covers light barriers, light curtains and light grids – defines only types 2 and 4. Following modification of the standard, type 2 light grids can now be used only in PL c applications, while type 4 light grids can still be used for PL e. Type 3, which has not been commercially available until now, is assigned to performance level d. Users previously had to switch to type 4 to satisfy the PL d requirement.
The new light grids are said to be particularly suitable for manual workplaces, the infeed and discharge of materials, and for materials-handling robotic applications. With their 50g shock resistance, they are ideal for rugged industrial environments.
The type 3 light grids offer not only hand protection, but also finger protection up to PL d. They work with continuous single beams that eliminate “dead zones”. The light barriers can thus be used closer to an application, saving space.
The light grids are also said to reduce downtime. Built-in LEDs can be used to rapidly assess any faults responsible for a machine stopping.