There are numerous wiring systems for building automation networking. These include power lines, USB, Ethernet, fiber and others. Wired and wireless networks such as those for data are very common. These utilize UTP cables, fiber cables, Ethernet switches, wireless access points, and others in LAN and optional WAN configurations.
LANs interconnect the various devices in a building or office while WAN enables communication between different buildings and other resources such as Cloud, remote control devices or rooms. This allows facility managers to monitor and control the systems remotely using mobile or desktop devices over the internet.
While the devices and systems within the building communicate locally, they, in most cases, do not require the internet. However, the WAN does require this for the system to connect to the external world.
Wireless building automation networking
Today, most manufacturers are developing products that use the standard wired and wireless Ethernet networks using the same IP protocols as our computers. Wireless technology, in particular, is replacing the traditional wired infrastructure due to its convenience, ease of installation and flexibility. Wireless provides benefits such as fewer materials, wires, conduits and labor. In addition, it’s more convenient and easy to expand and includes areas that would be otherwise difficult to wire. But even with its many benefits, engineers are concerned about its reliability, which is lower compared to wired systems.
In addition, the technology has a number of limitations. These include lack of clear wireless standards, the inability for the signal to reach some locations within the building, sensors without Wi-Fi capability, power issues and more.
Already, there are three competing wireless standards, including standard WiFi, Bluetooth Low Energy, and Zigbee.
Powering BAS components
Most BAS utilize low-power DC devices with some of them running on power from the Ethernet wiring. Therefore, low voltage wiring is commonly used to connect the controllers, sensors, transmitters and other building automation devices. However, powering wireless sensors is usually a challenge.
While mobile devices and routers, which are few in numbers, can be recharged or placed near power points, most sensors use non-rechargeable batteries. Due to the nature and a large number of wireless sensors in big buildings, it is practically impossible to locate all of them near power points. Moreover, sensors should have the ability to reliably and safely work with and without utility power.
The best approach to completely eliminating wires, both for signal and power is to use wireless sensors with long-life batteries. If possible, include energy harvesting capability.
Challenges in connecting various devices
The majority of contractors and building owners are creating networks that interconnect all the components. These provide a single point of monitoring and control the different types of devices, sensors, and equipment.
While wiring the building during the construction phase is the ideal situation, modifying or upgrading existing systems can be challenging.
As the building gets bigger and more complex, so does its automation, making it a real task to interconnect all components. It may require hybrid systems consisting of the UTP, RS-232/RS-485, wired and wireless networks, and a variety of protocols. However, there is still a need to unify all these. It’s best to have a single point of managing and controlling the devices regardless of the style, location, function, and type of network.
Building automation networking communication protocols
As building automation evolves, there are now industry standard network protocols that allow people to interconnect components from different manufacturers. The three most commonly used interoperable protocols in use today include:
- Building Automation Controls Network (BACnet): The BACnet network protocol is popular in connecting multiple devices in a building. It allows communication between devices using the existing LAN and WLAN infrastructure. It does not have any charges or licensing fee and is the most popular.
- Modbus: This is a simple protocol for connecting electronic equipment in both building and industrial automation. The protocol is based on traditional Ethernet and serial communication protocols and has no licensing fee.
- LonWorks: This is a low bandwidth communication protocol that connects devices through fiber optics, power lines, and other networking media. It also uses several network interfaces including the U10/U20 USB networks. This is a proprietary protocol with a limited number of users which are mostly manufacturers.
Benefits of building automation networking
Building automation enables efficient control of the various systems and conditions in the building. This allows the occupants and owners to save costs, while improving comfort and living conditions. It adds the ability to automatically monitor and adjust the lighting, air conditioning, heating, ventilation, security and other parameters. Specific benefits include:
- Ability to control systems throughout the day and night including weekends and holidays.
- Reducing energy use helps owners or tenants to save on electricity and other energy bills, reduce operational costs and increase efficiency.
- Facility usage data helps managers to make better decisions when scheduling lighting, HVAC, security and safety systems.
- Improved comfort for occupants and enhanced environment for equipment.
- Reduces the building’s contribution to environmental degradation.
Building automation offers several benefits to the owners and occupants of the facilities. It allows the savings of resources such as energy and water while improving the conditions and comfort of the space.
As building automation networking evolves, equipment and applications from different manufacturers are able to work together via standard interfaces and protocols. This allows consumers to benefit from the latest technology and decreases our ecological footprint.