FM Articles

The Benefits of Wireless Controls for Building Automation


Wireless connectivity is no longer something that is “nice to have” in American schools and hospitals, and the need to connect is becoming more essential every day. Students, teachers, healthcare professionals and administrative staff count on reliable, high-speed and secure wireless technologies to both connect with each other and to access the wide range of applications and information on their school or hospital computer network.

Not surprisingly, wireless communications technology also has entered the world of facility management. Wireless building automation system (BAS) technologies offer a wide range of advantages over hard-wired systems including lower cost, greater flexibility and higher reliability.

Wireless BAS solutions are enabled by building systems and components that use direct digital control (DDC) technology, which allows centralized control and interoperability. State-of-the-art wireless technologies connect the BAS with mission-essential building systems, including the heating, ventilation and air conditioning (HVAC) systems and components.

The most advanced facility management systems use the building automation and control network (BACnet®) protocol and ZigBee® Building Automation standards.

Wireless Solutions Connect Building Systems
With BACnet, the BAS can communicate directly with various building systems including HVAC, lighting, access control and fire detection, among others. ZigBee provides a global interoperability standard and allows secure and dependable monitoring and control of building systems. ZigBee is the only wireless mesh network standard for commercial buildings that is approved by BACnet.

Wireless building management technologies also meet Institute of Electrical and Electronics Engineers (IEEE) standards, which make sure that the wireless BAS system will coexist with other wireless communications systems used in the building, including Bluetooth® and Wi-Fi. Adhering to various industry standards ensures that the BAS technologies provide secure and reliable wireless monitoring and control over today’s hospital and school building systems and those that will be developed in the years to come.

The combination of BACnet and ZigBee offers redundant, self-repairing mesh technology to keep wireless communications links connected. This is accomplished by a feature that automatically routes signals around obstructions, which provides a vital advantage, compared to conventional hard-wired applications. Hard-wired networks fail when wires are accidently cut, damaged or disconnected.

Recent advancements in wireless BAS technology include reductions in power consumption and longer-life batteries for remote sensors. In addition, using high-performance routers has doubled the range of previous-generation equipment, which makes installation easier and reduces installation and operating costs. The use of routers with greater range also eliminates the need to install repeaters to spread the signal throughout the hospital or school building.

Wireless Controls Offer Distinct Operating Advantages
Wireless BAS solutions are more reliable and offer better performance than conventional hard-wired systems. These solutions are more flexible, can be installed in less time and cost less to install and maintain than the alternative wired approach.

Going wireless offers three major advantages for healthcare and educational facility management teams:

On-Time & On-Budget Project Completion—The wireless approach simplifies building control projects in both new and existing structures, improving the efficiency and reducing the cost of the project and making life easier for building operators and their construction industry partners.

Organizations benefit because the time and expense required to engineer, estimate and manage project tasks is significantly reduced. Labor costs and the chance of delays also are reduced because there are no wires to be pulled, tested and repaired.

Zone sensors, controllers and other hardware can be installed quickly and efficiently. Hardware can be attached directly to the wall or ceiling without penetrating the structure, reducing the incidence of dust and other airborne contaminants that can negatively impact indoor air quality (IAQ). Clean up is easier and less expensive.

Sensors can be positioned wherever they are needed and can be easily relocated to improve data collection and occupant comfort. The cost of placing and relocating sensors is much less than in a hard-wired application. For Example, in the experience of one global provider of indoor comfort solutions and services, it takes less than 15 minutes per zone to relocate wireless sensors, compared to about 90 or more minutes for wired sensors.

Time savings is especially important in the healthcare or educational environment in which contractors often have a small window of time to complete their work without disrupting normal operations.

Easier Problem Solving—Building operators find it easier to solve problems in a wireless environment because there are no cut or compromised wires or bad connections to bring the network down. Wireless networks operate with wireless mesh that provides multiple data paths to keep the system up and running reliably.

It is easy and inexpensive to relocate devices to improve sensing and control, even after the initial installation is completed. During the building design phase, it is nearly impossible to know exactly where sensors should be placed in a given room because the designer does not always know where equipment will be placed.

For example, the effectiveness of an HVAC sensor or thermostat may be reduced if it is positioned near a heat-generating piece of equipment, like a copy machine. This can cause overcooling of the room, which can affect occupant comfort and waste energy.

There may be business or aesthetic reasons why equipment cannot be moved. However, moving the sensors is easy and inexpensive because their location is not governed by wire. Wireless solutions make it easy to reconfigure or remodel rooms, departments or whole floors, because sensors and controllers can be moved with minimal cost and effort.

Lifecycle Savings—The use of wireless significantly reduces the cost of building control projects for new and existing buildings. Design and engineering processes take less time, which translates into less cost. Fast, trouble-free installation contributes to on-time, on-budget project completion. Certain steps in the rewiring process – such as the pre-installation site survey – can be totally eliminated, saving both time and money.

Cost efficiencies are also achieved in material and labor, because the process of establishing a BAS communications link is so much simpler. Operators and designers are not “bound by the wire” in placing devices. Sensors and user interface devices can be placed where they will have the greatest impact on building performance, occupant comfort and energy efficiency – on columns, cubical walls or anywhere else they can detect the true conditions inside the building.

Building automation components and devices often need to be moved as the building’s purpose, configuration or occupancy change. This process is much simpler with a wireless solution. Because it is much quicker to reconfigure a wireless BAS communications network, changes are easier, quicker and cheaper to make. In addition, they are less likely to disrupt hospital or school operations. Wireless BAS networks also contribute to lifecycle energy efficiency and operating cost savings. They are less expensive to maintain and enable operators to place sensors and other devices where they will have the greatest impact on organizational efficiency and effectiveness. Growth in the use of wireless technology in the healthcare and educational environments, combined with significant improvements in wireless performance and reliability, have made this the ideal time for organizations of all kinds to consider the advantages of a wireless solution for both new construction and retrofits.

Wireless solutions can help facility managers overcome retrofit difficulties and reduce costs in existing buildings, making upgrades to the BAS more cost effective. Enabled by wireless solutions, facility management teams can do a better job of improving comfort, reducing energy use and operating costs, shrinking their environmental footprint and creating a positive environment for students, patients and other building occupants.

Jim Kohl is senior product manager for Trane, a brand of Ingersoll Rand.