Understanding common household light bulb shapes, sizes, and styles is important whether you’re converting outdated incandescent fixtures into energy-efficient ones or using LED bulbs for new-construction applications. Every light bulb has identifying characteristics that are represented by a letter or series of letters and a number; these are known as light bulb codes. The letter or letters in a bulb code indicate either shape or special features such as reflector type. Numbers in a bulb code indicate size in millimeters or eighths of an inch. These codes will tell you if a bulb will fit in your fixture and if it’s the right shape.

For every light fixture or application, there’s going to be a specific bulb or light bulb shape that will fit best and provide the right type of light. If you understand bulb codes, it’s easy to look at a light fixture and know right away what kind of bulb you’ll need.

Let’s talk about light bulb groups, their bulb codes, and what applications those bulbs are typically used for.

Standard/arbitrary (A) bulbs are the most widely used and thought of when it comes to household lighting. These bulbs work well for a variety of applications, such as ceiling lights, lamps, vanity lights, kitchen lights, closet lights, porch light fixtures, and so many more.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

A15 bulb: 15/8 = 1-7/8″ diameter

A19 bulb: 19/8 = 2-3/8″ diameter

A21 bulb: 21/8 = 2-5/8″ diameter

A25 bulb: 25/8 = 3-1/8″ diameter

Most common base types:

Globe (G) bulbs have a full, round shape and are available in various sizes. They can be used for many applications throughout the home, such as foyer lights, kitchen lights, chandeliers, and ornamental fixtures. The most common type is the large G30 bulb, which is used in bathroom and makeup vanities.

Depending on the bulb, numbers in each code can refer to the bulb’s diameter in one-eighths of an inch or in millimeters.

G11 bulb: 11/8 = 1-3/8″ diameter

G14 bulb: 14/8 = 1-3/4″ diameter

G16/G50: 16/8 = 2″ diameter

G60: 60 millimeters = 2-3/8″ diameter

G25/G80: 80 millimeters = 3-9/64″ diameter

G30: 30/8 = 3-3/4″ diameter

Most common base types:

All of the bulbs in these groups resemble the shape of a candle flame and are often referred to as candle bulbs. Conical (C) bulbs are shaped like a cone. Conical angular (CA) bulbs are shaped like a cone but have a bent tip. Blunt-tip (B) bulbs are very similar to C-type bulbs but have more of a torpedo or bullet shape. These bulbs can be used in chandeliers, wall sconces, pendant lights, night lights, decorative light strands, holiday light strands, and other decorative home lighting applications.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

B10 bulb: 10/8 = 1-1/4″ diameter

CA10 bulb: 10/8 = 1-1/4″ diameter

C7 bulb: 7/8 = 7/8″ diameter

C9 bulb: 9/8 = 1-1/8″ diameter

C15 bulb: 15/8 = 1-7/8″ diameter

Most common base types:

BR stands for bulged reflector. Traditionally, the inside surface of an incandescent BR bulb is covered in reflector material that is used to gather and cast a wide beam of light away from the bulb. LED BR bulbs don’t require the reflector material. These bulbs can have a frosted, clear, or patterned dome-shaped lens that diffuses light and provides a gradual fade into nonilluminated areas. BR bulbs also produce less shadows when compared to PAR bulbs. They’re a bit longer than PAR bulbs and tend to protrude from light housings but are used in similar applications, such as track lights, recessed lights, display lights, or can lights.

BR20 bulbs are often referred to as R20 but have the same characteristics of other BR bulb types. The R stands for reflector.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

BR20/R20 bulb: 20/8 = 2-1/2″ diameter

BR30 bulb: 30/8 = 3-3/4″ diameter

BR40 bulb: 40/8 = 5″ diameter

Most common base type:

Multifaceted reflector (MR) bulbs are small in size with a reflective, faceted interior. The facets create a concentrated beam of light that can be displayed in a narrow spot or wide flood beam pattern. Because of the directional light they provide, MR LED bulbs don’t require the facets but often still have them. These bulbs are available in a variety of colors and can be used for many applications, including track lighting, recessed lighting, desk lights, and display case lighting. Many MR bulbs operate on low-voltage wiring systems, which makes them great for outdoor and landscape applications such as driveway lights, path lights, gazebo lights, paver lights, and malibu lights that have weatherproof housings.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

MR11 bulb: 11/8 = 1-3/8″ diameter

MR16 bulb: 16/8 = 2″ diameter

Most common base types:

Tubular (T) bulbs come in a variety of lengths and widths. Depending on their size, these bulbs can be used in applications ranging from chandeliers, wall sconces, and pendant lights to basement and garage troffer light fixtures.

Numbers in each code refer to the bulb’s diameter in one-eighths of an inch.

T7 bulb: 7/8 = 7/8″ diameter

T8 bulb: 8/8 = 1″ diameter

T10 bulb: 10/8 = 1-1/4″ diameter

T14 bulb: 14/8 = 1-3/4″ diameter

Most common base types:

Winter is slowly taking over here in Maryland. And after the summer we had, no one’s complaining (just yet)! But while the holidays offer up lots of fun, and the cool of winter is currently quite welcome, the season has its fair share of electrical worries unique to itself. Want to be prepared for anything winter might toss your way? We can arm you with some common winter electrical problems in Baltimore. Read on with the electricians at Kolb Electric!

Need the services of a dependable Baltimore electrician? Contact Kolb today for any electrical repair, installation, or service you need!

Keep wary of these concerns, and you’ll find yourself comfortably enjoying the finer points of the season this year:

Is your home prepared and equipped for all of your burgeoning winter electrical needs? If not, contact a Baltimore electrician from Kolb Electric today to get the dependable services you need!

To be honest, I’ve always liked the look of CFLs. Yes, there have been Image via Plumen.com

The light bulb itself does everything you’d expect it to. It’s 80% more efficient than a standard incandescent light bulb, and it’s expected to last 8 years. However, this isn’t a light bulb you want to hide behind some shade.

Mechatronics, or mechatronic engineering combines mechanical and electrical engineering to design innovative products and systems. These systems must rely on mechanical and electrical components working together in harmony.

The list includes DVD disc drives, anti-lock braking systems, manufacturing, electric motors and clothes dryers, among others. These devices require electronic controls and feedback systems to interact seamlessly with their mechanical design.

Motor control systems operate by using a programmable logic controller or PLC. This system allows advanced programming and algorithms to dictate a motor’s behavior. Therefore, they can be programmed to control multiple motors or VFDs. A robotic arm or a large factory machine is a good example of this.

In addition, PLCs can accept inputs from a wide range of sensors and switches. This allows precise feedback from the machine it controls. Furthermore, it executes built-in software.

The smallest high-precision motors, DC motors, found in computer hard drives and DVD readers. Due to their miniaturization, they can be easily controlled by computer software to perform nearly any imaginable task. A battery powered quad-rotor drone offers us a prime example of DC motor control. Accelerometers and gyroscopes feeding data into a computer controller adjust the speed of each motor independently to keep the drone flying level.

A simple technology that combines electric motors with feedback control, known as servomechanisms, provides valuable information. They utilize a small electric motor, gearboxes, and a potentiometer to produce accurate position feedback to the motor itself. This ensures that the motor has moved to the correct position. Thus, precise movement control of a motor is possible. Applications of servos include RC car steering, fly-by-wire systems in aircraft, robotics, and industrial control valves.

Servos communicate with computer systems, allowing them to be part of larger mechatronic systems, so they can be controlled by PLCs and computer algorithms.

The field of mechatronics constantly evolves. Therefore, as it does, it incorporates cutting edge computer software and mechanical design, bringing to life new inventions. These breakthroughs make modern-day living much easier and more fun.