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AUGMENTING BACnet WITH LoRaWAN ® WIRELESS IOT www.lora-alliance.org Case Study: Voytech VOYTECH'S INTEGRATION PATHWAY The UK control and monitoring specialist Voytech says that integration of LoRaWAN within a Buildings Management System (BMS) is a robust route to expanding the data available to the system without incurring excessive installation costs. The challenge any BMS project will face is how to extend the capabilities of the system using an inherently flexible wireless application like LoRaWAN, and continue to leverage the capabilities of the installed environment of BMS devices, which mostly support the BACnet protocol. A conversion gateway between the LoRaWAN and BACnet environments may be necessary, but as Dr. Richard Fargus of Voytech Systems argues, "BACnet is actually ideal for integration with LoRaWAN as it allows low level integration of individual data values such as binary statuses, temperatures and setpoints." Voytech has recently demonstrated an integrated BMS/ LoRaWAN solution for central Heating, Ventilation & Air Conditioning (HVAC) control using a conventional BMS and a distributed heating system consisting of 60 control valves. The Voytech Sitelink Controller allows demand and temperature information to be transmitted to the BMS, and allows BMS control commands to be sent to the LoRaWAN devices. Dr. Fargas says that this integration option is attractive because it is best implemented as an on-site solution, and is cost-effective as long as the LoRaWAN devices are correctly pre-configured for easy installation. "The installation can be installed and commissioned by non-specialist electrical and controls contractors," says Dr. Fargas. "But it is essential that device installation is as 'plug-and-play' as possible, otherwise the potential cost-savings of LoRaWAN may not be realised." "This solution achieves complete control of central HVAC plant and integration of distributed room controls without the need for any wiring outside of the plant-room," adds Dr Fargas. "This results in significant installation cost savings while also reducing running costs by allowing more intelligent control of occupied spaces." + COMPLEMENTARY NETWORK: CREATE VIRTUAL BACnet DEVICES In a complementary network, an independent LoRaWAN network is introduced whether in a new-build or on top of an existing system of BACnet devices. The LoRaWAN network of devices communicates on its own set of protocols and connects to the building management system through a dedicated server that makes any device in the LoRaWAN network appear to be a BACnet device sending BACnet messages. The LoRaWAN server can be hosted in the cloud, or on-premises if security demands. Any LoRaWAN device can be added at will, including in locations where line-powered native BACnet devices would be too impractical or too costly. Yet no retrofitting of the buildings management system is needed – all the system sees is an additional set of BACnet devices that just happen to be virtual, thanks to LoRaWAN.

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