The Metasys N2 protocol was developed by Johnson Controls and is a communications protocol network designed to interface with Johnson Controls devices. Metasys N2 is defined around the RS-485 data communications standards. Metasys is primarily used in building automation, and as such Metasys networks and devices compete directly with LonWorks in the building automation industries.
Metasys N2 operates as a master/slave protocol that has only one master: thus you can’t have multiple devices performing this function within the same network.
Metasys Wireless, Compatibility and Interoperability
One of the great strengths of the Metasys network and devices touted by creator Johnson Controls is the wireless capabilities of Metasys. Wireless technology can be incorporated at any or all levels of a Metasys system: everything from the field controller level to the user interface to the building infrastructure.
The other great strength of Metasys is it’s backwards compatibility. Metasys systems are compatible with all past technologies and Johnson Controls promises equal compatibility with all future versions. Further Metasys has excellent BACnet interoperability.
Metasys Applications
The Metasys protocol is used primarily within building automation, and as a building automation network control protocol competes directly with LonWorks. While LonWorks extends to other areas, from train control to city-level automation, Metasys is more targeted to building automation. As such Metasys applications include the following:
- Elevator controls
- Building lighting control
- Building security system control
- Control of heating and air conditioning systems
Metasys is used throughout just about any industry that includes large-scale buildings, which benefit from automation both in ease of use/reduced personnel and the substantial energy cost savings that building automation brings with it. Metasys is used in everything from ice rinks and school to air ports and shopping malls.
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