THREE DIMENSIONS AND INDICATOR LIGHTS

THREE DIMENSIONS AND INDICATOR LIGHTS
Since the introduction of the first infrared beam grid systems, various improvements have been incorporated to enhance passenger safety.
Three dimensions principle
Perhaps the most significant of these is the “three dimensions” principle, which enables the two-dimensional grid to be extended into the approach zone in front of the doorway. Adding this feature makes the basic beam grid much friendlier to slow-moving passengers and hospital beds, so it is ideal for sheltered housing, hospitals and hotels.
Passenger detectors based on the three dimensional principle were first introduced in the UK during the mid 1990s. The principle used is to project beams of infrared light from the emitter channel into the space ahead of the door, and then look for reflected light entering the receiver channel. The reflections are normally from approaching passengers, but might be from hospital beds or a porter’s trolley. The range is typically up to about one metre from the door surface and gives plenty of time for the doors to reverse out of the way of the approaching person or trolley. The technology can also help to prevent door damage from collisions with heavy beds.
Indicator lights
Another innovation is to inform the passenger when the doors are about to close. These devices incorporate indicator lights into the detector channels, usually in the form of red and green LEDs with diffusers, and provide visual warnings to the approaching passenger. The usual implementation is to have steady green lights for ‘safe to enter’ and flashing red lights for ‘door closing’, but many variations of colour and function are possible.
The humble mechanical “safety edge” has come a long way in the last 50 years and is now a sophisticated and essential part of a lift car. It seems likely that these devices have a long and successful period still ahead of them.Welcome to our website, thank you to click our wab! www.mozitor.com