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Broadly defined, by the Global Standards Initiative and Harvard Business Review, as the internetworking and intelligence-enabling of physical devices, the Internet of Things (IoT) enables organisations to get far more from assets.

All aspects of HVACR equipment, from lighting, boilers, air handlers and electrical panels should be networked for optimal results, to give users the ability to communicate with remote monitoring and facility management software solutions.

With the right control and monitoring technology, users can collect and analyse HVACR operating data from across their building or estate. Giving both service providers and end-user organisations the opportunity to achieve heightened performance and safety compliance, while protecting assets and reducing operating costs.

Building automation systems (BAS) are a combination of varying equipment and devices, all of which communicate across a local or broader network. The way in which these devices communicate is called the protocol, either open or proprietary.

Typically, manufacturers that produce building automation equipment select which protocols their equipment will conform to. This means that users of this equipment are choosing not just the solution, but the protocol used to support it. Companies who produce proprietary protocol systems typically do not disclose their technical information and as such customers are forced to acquire all the components they need from one supplier. Arguably, proprietary protocols lock customers in and take away their freedom of choice to expand their system with alternate suppliers.

Open protocol systems offer a higher degree of flexibility. Customers can choose from a variety of different suppliers for the solution that best matches not just their technical requirement, but their financial needs also. Allowing them to incorporate existing assets, through integration with third-party systems, or assets that they choose to purchase from other suppliers who also support open protocols.

Selected protocols, BACnet™, Modbus® and LonWorks®, for example, are compatible with almost every type of building automation equipment. Which is why most building automation systems are based on one of these three protocols

Why Open Protocols?

  • Compared to traditional BAS, open protocols offer scalability and reduced cost of linking equipment on-site.
  • Increased networking flexibility, with more integration options between existing and new infrastructure.
  • Ability to switch between networking mediums, for example, Modbus TCP/IP or RS485, expands usability and reduces set-up and installation time.

Truly Open Protocols

It is also worth noting that while some protocols such as XML, Web services, HTTP, and HTTPS are genuinely free and open. Other protocols may force developers to become members of organisations with annual fees and hidden costs. These costs are ultimately passed on and beg the question, are the protocols truly open or are they open with strings attached?

Open Protocols from RDM

Controlling multiple aspects of the heating and ventilation system, RDM solutions help customers worldwide to apply predictive or intelligent maintenance, be safety compliant, protect assets and manage energy. We design and manufacture the full range of hardware and software for some, part or all end-to-end control and monitoring solutions. Which means that customers have one port-of-call for their control solution needs, requirements and support.

Through the adoption and implementation of IP, XML, plus the optional plug-in connectivity with BACnet and Modbus, amongst other protocols, RDM products can communicate across open protocols and non-proprietary networking communications.

Furthermore, RDM do not charge an annual maintenance or license fee for any of our protocol activations, The licence is for the life of the hardware, and most of our hardware products are backed with a best in class five year warranty.

In a market that continually demands visibility and accessibility, RDM stands at the forefront of suppliers that not only meet but exceed end-user expectations. Our mobile, entirely web-based protocol is unmatched in the building and energy monitoring arena.

Unlike competing products, DMTouch and our range of Intuitive controllers are based on our XML open protocol platform and will communicate with both open and, after appropriate activation, proprietary protocols.


Extensible Markup Language (XML) is a metalanguage, similar to HTML, which allows users to define custom markup languages. Typically used to display information on the Internet, XML encodes information in a format that is both human-readable and machine-readable. Facilitating the communication of disparate systems, by exchanging XML messages.

  • Increases simplicity, generality, and usability across the local network
  • Information coded in XML is easy to read and understand, processed efficiently by computers
  • XML documents can contain any data type — from multimedia data (image, sound, video) to active components (Java applets, ActiveX)

Web Services

  • Enables communication between virtually any device, system or application
  • Future-proof method of integrating and interoperating
  • Easy to implement in most applications

In building automation, Web Services and XML are often used to integrate building systems that have various protocols in use. For example, an enterprise with a mixture of BACnet and LonWorks based facilities could use a Web Services application to integrate the information from both networks and provide unified reporting and analysis. Extremely open web-based standard.


BACnet was designed to allow communication of building automation and control systems for applications such as heating, ventilating, and air-conditioning control (HVAC), lighting control, access control, and fire detection systems and their associated equipment.

  • BACnet™ has features and capabilities that can be tailored precisely to the needs of building automation systems that other protocols do not.
  • Widely adopted by many of the leading manufacturers.
  • Five interoperable areas – data sharing, alarms and events, scheduling, trending and device management.
  • Negatives include: annual membership and product approval costs.


Widely adopted across a wide range of industries, Modbus® is most commonly used within building automation systems. Truly open and said to be the most frequently used network protocol in the industrial manufacturing environment. It is typically used to transfer analogue I/O and register data between control devices and as a standard for connecting of industrial electronic devices.

  • Proven, with an estimated seven million Modbus nodes in-use across Europe and North America
  • Simple to set-up and manage.
  • Cost effective as it uses standard Ethernet or RS485.
  • Widely adopted by many manufacturers.


LonWorks® is a widely used standard for many types of control applications, including building automation. Created by Echelon in 1988, it was accepted as a standard by ANSI for control networking in 1999. The vast majority of LonWorks® devices involve buildings projects, including HVAC and lighting. It is also used for many other applications including transportation, utilities, and process control.

  • Developed for building automation
  • Proven, with millions of devices already installed
  • Standard applications ensure consistency regardless of the supplier
  • Supported by hundreds of manufacturers
  • Simple installation
  • Flexible connectivity

What Next?

Download the whitepaper Mapping the HVACR Internet of Things >>


IOT | Posted on 10 May 2018


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