The wireless concept has found its way into building controls, initially penetrating the lighting market, but expected to expand to other building systems. And one of the main drivers of the wireless building controls movement is ZigBee.
ZigBee is an open set of high-level communication protocols designed for use with low-power digital radios that are based on the Institute of Electrical and Electronics Engineers (IEEE) Standard 802.15.4. It is intended specifically for small building devices such as thermostats, lighting controls, ballasts, environmental sensors and medical devices. The protocol is meant to offer short-distance, low-speed transmissions that require little power; devices are now being designed with batteries that provide power for six months to two years.
ZigBee was created to link devices without the expense of running wires between them. It is made for two-way communication among devices, and can be used to build a self-organizing, self-healing mesh network, where if one device or node loses power, the signal can be transmitted to an alternate node, thus maintaining the chain of communication.
And it has quite a backing. The ZigBee Alliance is a group of more than 100 companies working to develop standardized application software on top of the IEEE 802.15.4 standard.
A supportive protocol
ZigBee supports users in many ways, including helping to reduce the initial installation cost of a control system while saving money on system operation and maintenance. Additionally, ZigBee offers:
Flexibility and scalability. As the requirements of a building change, so do the system requirements. ZigBee allows users to make changes and modifications to their building systems without having to “re-rewire” any of the system devices.
Design and installation time reduction. Designing and installing systems in buildings is a costly endeavor; control system devices currently require low-voltage wires to be designed and installed in order to communicate with each other. However, ZigBee removes the complication of control wiring throughout a building, enabling devices to communicate wirelessly.
Interoperability. The goal of the industry was and still is to make system devices communicate with each other and to make buildings more efficient. Unfortunately, many proprietary protocols were developed by individual manufacturers, which made it very difficult to make multiple systems interoperable. ZigBee makes it feasible for devices to communicate and work with each other. It also makes it easy for devices to communicate with other unrelated devices (HVAC, lighting) without relying on network wiring.
The future of ZigBee
ZigBee is shaping up to be the next generation of building system protocols. Over the years, manufacturers have developed many protocols, including wireless, but ZigBee is the first of its kind to address the problems of interoperability, battery life and cost. Many manufacturers are in the process of developing their control offerings using ZigBee and are just beginning to deploy them to the market.
ZigBee advantages
Flexibility and scalability
Reduction in design and installation time
Interoperability
