By Al Presher – Banner’s proprietary wireless technology used in the new photoelectric sensors is based on the 2.4 GHz ISM band, and creates a frequency-hopping, spread spectrum solution. The system doesn’t use Zigbee, WiFi, or other standard radio communication architectures because those solutions can’t provide all the characteristics that this application requires. Specifically, they are not designed for small amounts of data, exceptionally low power, deterministic data transfer, and very long range communications.
A wireless system design is much less expensive than implementing slip rings using cable trays and flexible cables. more> http://tinyurl.com/d6g3snu