Ceiling fans are sometimes looked over when decorating a home. Besides of freshening a room, fans complete a room design and composition. It’s important to understand how size and height affect the fan’s efficiency and overall look of a room. A ceiling fan that’s too big will overpower the room’s design and visually pull the ceiling downwards; a fan that’s too small won’t properly circulate the air.

By Maddie Ogletree

What goes on behind the scenes of March Madness often goes unmentioned. The action is up front, while the lights and cameras are working hard in the background. Some major aspects of the March Madness experience happen without a hitch, and sometimes they’re the hardest to manage. No wonder there was a lighting mishap during the Super Bowl in 2013.

Amidst all the madness this March, take a moment to notice the electrical components powering the stadiums, such as:

The music and sound effects heard during the event can all be attributed to the thousands of cables running throughout stadiums across the country, linking the AV control rooms to the speakers above the court. When stadiums are built, every single cable is intricately installed to enable you to experience the sights and sounds of March Madness the way you’re able. Lucas Oil Stadium in Indianapolis, host of the Final Four and championship games, reports about 764,000 cables in their audio and video setup alone!

To ensure that the arena doesn’t go dark mid-play, backup generators are a must to make sure everything runs smoothly during the games. It might not be the first concern to pop into your mind, but in an emergency or accidental power failure backup generators are the heroes of the game. Most arenas are prepared for these events and have multiple generators ready to go in the event of a power failure.

How the stadium stays perfectly lit is not often considered, but it’s a necessity for these games that can be tough to power. Recently, NRG Stadium in Houston, Texas updated their lighting to a more sustainable system. The new system draws 337 kilowatts of energy at full power – 60 percent less than their previous system. That’s huge, especially when their stadium now houses more than 65,000 LEDs. Imagine keeping all of those lights functioning properly during the entire South Regional game.

Keeping up with the scores at games is easy with the giant screens present at every modern sports arena. But most people don’t realize the energy that is needed to show those replays on the big screen. While it does take quite a bit of energy, arenas are starting to focus on using sustainable sources of energy. The Moda Center, which will be hosting second and third round games for this year’s March Madness, purchases 100 percent renewable energy programs.

Electric motors power everything from tiny electronics to massive industrial pumps. Yet, they all work on the same basic principles. Though AC motors seem ordinary, there are complex activities going on behind the scenes.

The simplest types of motors are three-phase AC motors. They convert a rotating magnetic field into mechanical rotation. The basic parts of an AC motor are the stator, rotor, bearings, drive shaft, and frame. The supply power is connected to coils of wire that are wrapped around laminated iron cores in the stator; the stationary part of the motor. When the coils of wire receive current, they generate a magnetic field known as poles. Each phase of power has the same number of poles; the poles are spaced evenly around the stator.

Historically, speed control of three-phase induction motors was very difficult. The only way to change the operational speed is to change the frequency of electricity supplied. Today, this task is accomplished by use of a variable frequency drive or VFD. This device is made of three main components: a rectifier, a DC-Link, and an inverter. The rectifier takes the incoming AC voltage and converts it to DC voltage that can be used by the electronics in the VFD. The DC-Link then uses capacitors to help smooth out the DC voltage from the rectifier and feeds it to the inverter.

The inverter then converts the DC voltage back to AC voltage. The inverter also controls the output frequency of the AC power by sending precisely timed pulses of DC power at specific voltages to rebuild the AC sine wave.

With a VFD, not only can the output frequency be controlled, but it can be slowly ramped up. This allows for smoother starting and can be adjusted to keep a motor spinning at a specific frequency. VFDs can produce three-phase power from a single-phase source, or even a DC source, to power highly efficient three-phase motors in locations without a three-phase supply. VFDs can also be incorporated into a PLC system to allow for automatic or remote control.

The combination of a VFD and AC motors offers a wide variety of functions and increased efficiency. Basic understanding of these technologies is essential for any electrician.