Top 19 Building Automation Interview Questions You Must Prepare 19.Mar.2024

Energy demand in buildings depends largely on the climate where it is located. Lighting typically consumes 30-50 percent of electric demand. Heating and air conditioning varies by region, but can consume 20-40 percent of energy (gas, electric, and oil). Office equipment typically consumes 25 percent of the electric bill. Demand can be reduced by scheduled off or setback periods, peak demand monitoring and load shedding, the use of drives and by applying hundreds of control techniques that are specific to the equipment being controlled.

Schneider Electric has more than 100 offices and partners throughout the U.S. to service any region of the country.

As with just about any other product, the cost of building automation can vary wildly. The reality is that the cost all boils down to the type of equipment you choose and the functions you need the equipment to be capable of carrying out. With that said, in new construction, building automation generally works out to be between 1% and 2% of the overall cost of the project.

Building automation most broadly refers to creating centralized, networked systems of hardware and software monitors and controls a building’s facility systems (electricity, lighting, plumbing, HVAC, water supply, etc.)

When facilities are monitored and controlled in a seamless fashion, this creates a much more reliable working environment for the building’s tenants. Furthermore, the efficiency introduced through automation allows the building’s facility management team to adopt more sustainable practices and reduce energy costs.

These are the four core functions of a building automation system:

  1. To control the building environment
  2. To operate systems according to occupancy and energy demand
  3. To monitor and correct system performance
  4. To alert or sound alarms when needed

At optimal performance levels, an automated building is greener and more user-friendly than a non-controlled building.

Schneider Electric offers several control product families and many types of controllers for virtually any building control need. The local Schneider Electric office or partner assesses the building’s energy profile, budget, and requirements to determine the best products or services required to meet the customer’s needs. Energy service programs such as Schneider Electric’s EnergyStep can help customers assess what type of energy conservation measures are necessary for both immediate and sustained savings.

As a global specialist in energy management with operations in more than 100 countries, Schneider Electric offers integrated solutions across multiple market segments, including leadership positions in energy and infrastructure, industrial processes, building automation, and data centers/networks, as well as a broad presence in residential applications. Schneider Electric has a division dedicated to serving the healthcare marketplace.

Basic BAS have five essential components:

  • Sensors — Devices that measure values such as CO2 output, temperature, humidity, daylight or even room occupancy.
  • Controllers — These are the brains of the systems. Controllers take data from the collectors and decide how the system will respond.
  • Output devices — These carry out the commands from the controller. Example devices are relays and actuators.
  • Communications protocols — Think of these as the language spoken among the components of the BAS. A popular example of a communications protocol is BACnet.
  • Dashboard or user interface — These are the screens or interfaces hum use to interact with the BAS. The dashboard is where building data are reported.

Most of the activity within a BAS takes place out of sight from a building’s occupants. The collectors are discreet, and the controllers and output devices are hidden from view, just as wiring and plumbing are.

Unlike our competitors, Octant Innovations’ building automation systems are factory engineered. This me that by the time your building automation system reaches you, you can rest assured that it has been control configured and tested in our factory to ensure ease of use and system efficiency. Also, we have ensured that our products and services are priced competitively, without reducing the quality of product or quality of service our customers receive.

Kevin Callahan, writing for Automation.com, points to the creation of the incubator thermostat — to keep chicken eggs warm and allow them to hatch — as the origin of smart buildings.

Like most technologies, building automation has advanced just within our lifetimes at a rate that would have baffled facility managers and engineers in, say, the 1950s. Back then, automated buildings relied on pneumatic controls in which compressed air was the medium of exchange for the monitors and controllers in the system.

By the 1980s, microprocessors had become small enough and sufficiently inexpensive that they could be implemented in building automation systems. Moving from compressed air to analog controls to digital controls was nothing short of a revolution. A decade later, open protocols were introduced that allowed the controlled facilities to actually communicate with one another. By the turn of the millennium, wireless technology allowed components to communicate without cable attachments.

Terms to Understand

At first, the terms building automation professionals use look like a big game of alphabet soup. There are acronyms everywhere. And as Lynxspring’s VP of Marketing, Marc Petock, pointed out on LinkedIn, some people treat many of these terms as interchangeable. Let’s clarify this issue now:

Building Management System (BMS) and Building Control System (BCS) — These are more general terms for systems that control a building’s facilities, although they are not necessarily automation systems.

Building Automation System (BAS) — A BAS is a subset of the management and control systems above and can be a part of the larger BMS or BCS. That said, building management and building automation have so thoroughly overlapped in recent years that it’s understandable people would use those terms interchangeably.

Energy Management System (EMS) and Energy Management Control System (EMCS) — These are systems that specifically deal with energy consumption, metering, etc. There is enough overlap between what a BAS does and what an EMS does that we can consider these synonymous.

Direct Digital Control (DDC) — This is the innovation that was brought about by small, affordable microprocessors in the ‘80s. DDC is the method by which the components of a digital system communicate.

Application Programming Interface (API) — This is a term common in computer programing. It describes the code that defines how two or more pieces of software communicate with one another.

What makes the terminology particularly complicated is that the technology evolves so quickly that it’s hard to know at what point a new term needs to be applied. Then, you also have professionals in different countries using different terms but still having to communicate with one another. Just be prepared for the terminology to be in a state of flux.

Measurement is a key component of any energy program in verifying that energy conservation measures are turning in the results that were predicted. The combination of metering and building automation system data logging takes measurements as frequently as necessary through the system network to produce energy use reports. These reports then permit before/after comparison of energy demand. By aligning this data with the time energy conservation measures that were put in place, the system verifies whether energy reduction actually occurred and why.

In the home and in smaller applications, building automation can be installed by the end consumer. However, this isn’t the most common way it’s done. Instead, building owners generally work with a contractor for the installation of building automation systems.

A well designed system effectively reduces energy consumption year after year. When a building automation system is installed in a building or office park, it is programmed by Schneider Electric to very tightly control every aspect of the building that consumes energy. These programs optimize the building to maximize the comfort of occupants while reducing energy costs (electric and fossil fuel). Ongoing changes and adjustments to the system continually refine energy conservation measures and report on any areas where energy use may be excessive.

Security is top of my mind lately, many of our BAS systems are sitting on a proverbial powder keg in Death Valley surrounded by chain smokers during the middle of summer. Ok, I may have a bit of a flair for the dramatic but when I can spend 3 minutes and find an Airport with its BAS exposed to the internet and the default login/password still in the system that might be something a end-user should be concerned about.

Ultimately, the return on investment you’ll realize is directly correlated to the energy and maintenance costs of the systems your building automation is designed to control.

Building automation is beneficial to both building owners and occupants. For building owners, automation helps to reduce the cost of equipment maintenance as well as reduce energy costs. For occupants, building automation helps to make the building more comfortable. Through controlled HVAC, ventilation, and more a comfortable atmosphere is automatically created.

The benefits of building automation are manifold, but the real reasons facility managers adopt building automation systems break down into three broad categories:

  1. They save building owners money
  2. They allow building occupants to feel more comfortable and be more productive
  3. They reduce a building’s environmental impact

Saving Money

The place where a BAS can save a building owner a significant amount of money is in utility bills. A more energy-efficient building simply costs less to run.

An automated building can, for example, learn and begin to predict building and room occupancy, as demonstrated earlier with the heated board room example. If a building can know when the demand for lighting or HVAC facilities will wax and wane, then it can dial back output when demand is lower. Estimated energy savings from simply monitoring occupancy range from 10-30%, which can add up to thousands of dollars saved on utilities each month.

Furthermore, a building can also sync up with the outdoor environment for maximum efficiency. This is most useful during the spring and summer, when there is more daylight (and thus less demand for interior lighting) and when it is warmer outside, allowing the building to leverage natural air circulation for comfort.

Data collection and reporting also makes facility management more cost efficient. In the event of a failure somewhere within the system, this will get reported right on the BAS dashboard, meaning a facility professional doesn’t have to spend time looking for and trying to diagnose the problem.

Finally, optimizing the operations of different building facilities extends the lives of the actual equipment, meaning reduced replacement and maintenance costs.

Typically, facility managers find that the money a BAS saves them will over time offset the installation and implementation of the system itself.

Comfort and Productivity

Smarter control over the building’s internal environment will keep occupants happier, thereby reducing complaints and time spent resolving those complaints. Furthermore, studies have shown that improved ventilation and air quality have a direct impact on a business’s bottom line: Employees take fewer sick days, and greater comfort allows employees to focus on their work, allowing them to increase their individual productivity.

“The value benefits average $25.00/ square foot,” writes Minnesota’s Metropolitan Energy Policy Coalition. “With decreased sick days trlated into a net impact of about $5.00/square foot and increased in productivity trlated into a net impact of about $20.00/square foot.”

Environmentally Friendly

The key to an automated building’s reduced environmental impact is its energy efficiency. By reducing energy consumption, a BAS can reduce the output of greenhouse gases and improve the building’s indoor air quality, the latter of which ties back into bottom-line concerns about occupant productivity.

Building automation systems generally maintain themselves; therefore, regular maintenance isn’t required. However, Octant innovations does provide updates as well as system enhancements to their customers.

Schneider Electric offers energy services that can profile the energy use at any building or set of buildings. These services include metering, auditing, remote monitoring, and methodical measurement of the complete building envelope and related systems. The results of this type of service are an energy efficiency report, likely areas of improvement, and the payback that can be expected.

A BAS is a network of small, dedicated microcomputers designed to control various parts of a building, such as lighting, heating, air conditioning, elevators, blinds, boilers, chillers, f, and other parts of the building infrastructure. A scalable and flexible building automation system is the foundation of any energy conservation program for a building.