When an energy management system needs to measure temperature at hundreds of points throughout a facility, a hardwired network is impractical and costly. Laying cable is disruptive to business, and changing equipment placement and floorplans may mean that a network configuration that worked yesterday also needs to be updated. That's why Vigilent systems incorporate wireless networking.
Robust and reliable wireless networking is essential in industrial environments, which typically have a large amount of radio frequency (RF) noise. This noise is created by servers, UPS inverters and building systems, as well as other wireless communications, such as WiFi and mobile phones, all of which create interference that can significantly degrade network performance.
Vigilent systems incorporate the industry's leading, industrial-grade, wireless mesh network technology – SmartMesh® from Dust Networks®. Built around Time-Synchronized Channel Hopping (TSCH), the technology combines time diversity, frequency diversity and physical diversity to assure reliability, scalability, power source flexibility and ease-of-use.
A SmartMesh network includes a wired network manager that monitors and manages network performance and relays data to the host application, and wireless network nodes (referred to as "motes") that relay data to and from each other and the manager.
The manager coordinates routing, aggregates packets, collects network statistics and handles all data transfers with the core Vigilent AI engine. It is wirelessly connected to its mesh network and directly connected to the server.
The network nodes are ultra low-power wireless transceivers that transfer data to and from integrated sensors or controllers, and use an on-board radio to send the packets to neighboring nodes. Each node passes the packet on to other nodes, in a series of "hops" that deliver data to their destination. Preconfigured nodes can be added to or removed from the network without disrupting communications, creating a highly flexible and scalable sytem.
The sensor nodes are used to collect temperature and other environmental readings, and are placed at strategic locations throughout a facility to measure input and output temperatures. Typically they are applied using Velcro® fasteners, and can be stuck on walls, racks or devices. Control nodes provide the connection to CRACs and AHUs, closing the loop for direct machine control.
Mesh Network – A networking technology in which each node may act as an independent router, allowing for continuous connections and reconfiguration around broken or blocked paths.
SmartMesh® – Wireless mesh networking technology developed by Dust Networks® to provide ultra low-power, highly reliable networking technology for embedded systems.
TSMP – Time Synchronized Mesh Protocol is a communications protocol for self-organizing networks of wireless devices called motes.
In actual deployment, the combination of Vigilent and Dust Networks technology has demonstrated very high reliability, with typical loss of just one packet in 220,000 delivered over a six-month period, and a battery life of up to 55 months.