This piece was originally published in the June 2018 issue of electroindustry.
Wayne Stoppelmoor, Manager, Industry Standards, Schneider Electric, Barry Coflan, Senior Vice President and CTO, Schneider Electric
Mr. Stoppelmoor chairs NEMA’s High Performance Buildings Council.
Mr. Coflan develops technology used in analytics, building management, power management, and smart home systems.
That’s a nice building management system (BMS) you have there, or is it a building automation system (BAS)? What’s the difference between a BMS and BAS?
There is no difference—BMSs and BASs are the same. Each is an integrated system of hardware and software to automatically monitor and control building systems such as HVAC, lighting, power, fire, access control, and security to optimize the building’s occupant comfort, energy performance, safety, and security. BMSs and BASs may be installed in any size building and integrated with many types of building systems. They provide a strong foundation for intelligent buildings that inspire occupant productivity and deliver optimal energy and operational efficiency.
Figure 1. BMS connected devices may include sensors, monitors, actuators, and controllers. All images courtesy of Schneider Electric
A BMS utilizes an enterprise-level software platform and connected devices (see Figure 1) to manage building operation. It receives input data such as air and water flow pressures, voltages, currents, temperature, humidity, and carbon dioxide to determine how the building is performing as compared to set parameters. It then provides control outputs to control damper and valve actuators, pumps, fans, motors, variable speed drives, chillers, boilers, and cooling towers.
A BMS will typically include graphical displays on a computer-generated dashboard that provide building performance information to facility operators.
What about a building energy management system (BEMS)? Is that a BMS also? No a BEMS is an integrated platform of hardware and software for monitoring, trending, and reporting energy usage.
Because of its focus on energy, a BEMS may include linked packages that assist in reducing energy consumption. One such package is fault detection and diagnostics (FDD), which may also be called building analytics. An FDD system is a cloud-based software platform (Figure 2) that utilizes building analytic algorithms to convert data provided by sensors and monitors to automatically identify faults in building systems and provide a prioritized list of actionable resolutions to those faults based on cost/energy avoidance, comfort, and maintenance impact
The FDD system assigns dollar values to identified faults to demonstrate the additional energy cost impact of not repairing the fault. An FDD dashboard goes beyond a BMS’s dashboard in that it shows not only what is happening but also why it is happening and repairs that should be made to reduce the building’s energy costs and improve occupant comfort.
An FDD system can detect preheat and cooling coils operating simultaneously (figure 3), leaking and malfunctioning cooling valves and coil valves, faulty control codes, ineffective air flow balance, and other energy wasters. By repairing identified faults, FDD systems typically have a payback of less than two years.
Figure 2. FDD data identify faults in building systems, allowing the system to prioritize actionable resolutions to the faults based on cost/energy avoidance, comfort, and maintenance.
Figure 3. An FDD system can detect preheat and cooling coils operating simultaneously.
Figure 4. An FDD dashboard shows not only what is happening but also why it is happening.
The NEMA Connection
NEMA staff and Members are exploring the possibility of creating a BMS Section to assist Members in the BMS industry.
The concept was discussed at the NEMA High Performance Buildings Council’s (HPBC) meeting during NEMA’s Annual Meeting in November 2017. NEMA staff then developed a scope and value proposition that was presented during a general interest meeting in April with several potential section members in attendance. There was enough interest in moving forward with creating a BMS Section that a small task group of likely section members revised the scope with anticipation of submitting it for approval from NEMA’s Section Affairs Committee.
In the building construction market today, integrating electrical power, BMS, energy efficiency, and electrical fault detection is technically feasible and creates substantial benefits for individual customers. To go beyond individual customers to achieve broad-scale market adoption will require that organizations such as NEMA develop new Standards and education programs for the building ecosystem.
A particular challenge faced by a NEMA BMS Section is breaking down siloed construction divisions that are organized around technologies (e.g., HVAC, electrical, and lighting). To meet this objective, the proposed section could expand NEMA’s traditional focus from a device-level focus to a system-level focus in the building management systems environment. This would entail working with NEMA Members to develop Standards, guidelines, and education programs to inform the market of the benefits of adopting them widely across the trades and subcontractors.
This approach offers an opportunity to unleash the influential power of NEMA to benefit its Member companies and their customers, as well as design firms, trades, and the building industry as a whole. This work will provide a far more efficient and resilient interconnected environment.
Figure 5. Construction sectors
Items under consideration for inclusion in the NEMA BMS Section scope include:
- Identification, definition, education, and standardization of topics related to building control systems with various deployment scales. This may include characteristics and requirements for hardware, software, and system attributes as they relate to factors critical for the entire building.
- The topics addressed by the section will be inclusive of small, medium, and large buildings as well as single and multisite campuses.
- Coordination with NEMA’s HPBC in its efforts to promote the adoption of technologies and systems that increase the energy efficiency, safety, resilience, sustainability, productivity, building security, comfort, and other emergent benefits for private/public commercial, industrial, institutional, and multifamily residential buildings.
- Development of guidelines for integrating devices and systems (e.g., meters, smart devices, lighting, and low-voltage power distribution) into a BMS.
- Maintaining the intersection of BMS with traditional energy distribution and distributed energy resources at the forefront.
- Integration with demand response; time of use; electric vehicle charging; renewable energy production; operation, information, IoT and edge technologies, and other emerging technologies.
- Work with mechanical, electrical, and plumbing (MEP) firms to develop guidelines/Standards for assisting MEP firms with the integration of mechanical and electrical systems with a BMS.
- Education and promotion through various avenues (e.g., white papers, blogs, and social media) to the parties (i.e., consultants, contractors, vendors, manufacturers, and end customers) involved in the design, installation, and operation of a building.
- Generation of proposals to expand the construction divisions to remove barriers to efficient cooperation between construction groups so that information flows effectively between the groups.
Items to be excluded from the NEMA BMS Section scope include duplicative protocol development, protocol/platform mandates, non-systems-related device requirements, and cybersecurity standard development.