Light Bulb Bases Explained | What You Need to Know

Light Bulb Bases Explained | What You Need to Know

January 12, 2021

Believe it or not, there are tons of light bulbs and base styles. You might think there are only a few varieties, but there are so many that come in all sorts of shapes and sizes. For bases, there are at least 70 styles. For bulbs, there are 20 main shapes and styles, but there are many more specialized ones. 


When you think of a light bulb, most people tend to think of the standard, rounded light bulb we use for lamps. That is just one of many different styles of light bulbs. And even with that being the most common bulb, there are plenty of different bases that can accompany it. 


The reason for having all of these different base styles is to be able to fit any electrical device. Any lighting fixture could need a completely different base than another fixture. For older, more antique pieces, this is especially important because they have less modern features. Even with more modern fixtures, they may need a unique base in order for the bulb to work. 


In this article, we will take a look at the four most common base types for light bulbs: screw bases, pin bases, 3-way bases, and lock-out bases. You should have a better understanding of each type and what purpose they serve. Read on to find out what you need to know about light bulb bases! 


Screw Bases

The screw base is the most common type of base for a light bulb. It is the traditional base you think of when you think about the standard rounded light bulb we use for lamps. Many bulb bases are similar looking, but are not identical. If it is not the exact base you need, it simply will not work for the light fixture.


Screw base bulbs are also known as Edison bulbs, named after Thomas Edison. Even though the screw base is the most common base, there are also a subset of different bases within the realm of screw bases.


The base type might be called medium, intermediate, or candelabra, amongst other types. The number in the name refers to how big the base is in millimeters. These types also vary in size, ranging from 12-40 millimeters depending on the type. For example, a candelabra screw base is 12 millimeters in diameter, while a mogul screw base is 40 millimeters in diameter. 


Some types, such as the intermediate base and the bayonet base, are very rare to find in the United States. They are both smaller bases meant for smaller bulbs. These base types are more common in Europe and Australia. 


Pin Bases

The pin base is the other main type of bulb base besides the screw base. They are different because of the way in which they connect the bulb to its source of electrical voltage. The pin base has two pins that stick out at the bottom. These pins are what connect the base to the voltage. The electrical current that lights the bulb flows through the two pins. 


Pin bases can be used in the following light types: MR16s, HID light bulbs (not all, only some), linear fluorescents, and plug-in compact fluorescent bulbs. The millimeter measurement for each base measures the distance between the two pins. 


The type of pin bases you can have include medium bi-pin, single pin, and double contact. This simply refers to the style of the base and how its pins are situated. 


3-Way Bases 

3-way bases have three contact wires that are on the light bulb base. These contact wires are in different positions on the bottom of the base. The base is composed of the following parts: the side of the base, plastic, solder ring, plastic ring, and the center solder circle. 


An electrical current flows through two of the contact wires. When the bulb is turned off, then there is no contact between the current and the solder points. When it is on, contact is established and it produces light. 


These are used for light fixtures that have three switch settings (low, medium, and high). Each switch creates a different current flow within the 3-way base, producing a light that is brighter or dimmer depending on what you need. 


Lock-Out Bases

Lock-out bases are used for CFL and CCFL light bulbs. This will help to make them compatible with certain sockets that have a lock-out disc inside them. Utility companies will have these discs inserted into the sockets to ensure you do not use incandescent / standard light bulbs in the future. 


This is because the light bulbs that are compatible with the base are made for energy efficiencies, which people typically receive discounts and rebates for having. This means no other lightbulb besides CFL and CCFL energy saving bulbs can be used. 


What Are the Best Light Bulbs Regardless of Base?

The best type of light bulbs, in general, are LED light bulbs. These bulbs are highly energy-efficient and cost-effective. LED is short for light-emitting diode. This type of light source is known as a semiconductor. This means when a current flows through the circuit, light is emitted. 


As a bulb, LED lights emit barely any heat or energy, which is one of the reasons why they are so energy-efficient. In fact, they use 75% less energy and last 25 times longer than incandescent lighting (the standard type of lighting used in light bulbs). Over time, LED lights could save you hundreds (and eventually thousands) of dollars on your monthly energy and electrical bill.  


Boundery has an assortment of LED light bulbs that are great for indoor or outdoor use. Whether you need it for a light fixture or for lights in the ceiling, these bulbs work great. You can also use them in garages, attics, and other dark parts of the house. 


Boundery’s EBULB Emergency LED Light Bulb is a great place to start if you are new to LED lighting. This bulb charges when in use and becomes an emergency source of light when you experience a blackout or power outage. It is the world’s first self-charging bulb that turns on automatically when your power fails. You will never have to worry about being in the dark again. This is huge for safety measures and security purposes, as well as convenience. 


Boundery’s Night2Day Smart Safety Bulb is another great choice. This light automatically turns on when it gets dark, and turns off when it gets light. This makes it ideal for outdoor light, perfect for patios, porches, garages, and to put over doors for nighttime entry and safety. It also makes things really easy for you, as you will never have to turn a light switch on and off again. This helps to keep electrical costs down because it will only turn on when it is actually needed.   


Final Thoughts

While we may only think of a few types of light bulbs off the top of our heads, there are so many. Different light bulbs all have different bases that come in various shapes and sizes. This is because there are so many differing light fixtures that have specific connecting spots for the light bulb bases. 


As we discussed, there are over 70 bases to choose from for light bulbs. The four most common types of bases that you will find in most hardware and home improvement stores are screw bases, pin bases, 3-way bases, and lock-out bases. Each base is a different shape and size, meant for a specific light bulb. 


Screw bases are the standard bases for light bulbs. They also have a subset of sizes for the base and different bulbs that match up with each base. Pin bases have two pins sticking out of the bottom, which help the electrical current flow into the bulb. 3-way bases are composed of three contact wires that allow the bulb to switch its light strength from low, to medium, to high. Lock-out bases help to ensure you only use energy-efficient bulbs in your home. 


At Boundery, we specialize in LED lighting and gear. We use the common screw base on the bulbs in order to fit most electrical fixtures. Our light bulbs use LED lights, which are the most energy-efficient and money-saving lights available. They are built for safety, because they charge when in use and turn into an emergency light during emergencies. Alternatively, they turn on in the dark and off when it is light. 





Sources:

  1. https://blog.litetronics.com/blog/light-bulb-bases-guide-part-1-screw-base-light-bulbs#:~:text=Screw%20bases%20are%20the%20most%20common%20light%20bulb,the%20electrical%20voltage%20connects%20to%20the%20light%20bulb
  2. https://www.superbrightleds.com/blog/understanding-light-bulb-base-types-screw-bases/5537/ 
  3. https://www.ledwatcher.com/light-bulb-shapes-sizes-and-base-types-explained/