The difference between a shunted and non-shunted lamp holder is how the electrical current flows through the fixture. The current flows through a single path in a shunted lamp holder, while in a non-shunted current flows through multiple pathways. If the wrong lamp holder is used, the likelihood of an early burnout of the bulb or short circuit is significantly increased.
What is a ballast?
Some lighting fixtures require a ballast to work. The ballast is the part of the circuit that alters the amount of electrical energy transferred to the light fixture. When the user switches on the light, the ballast instantly releases a high voltage to establish an arc between the contact points.
Once the connection is made and the light turns on, the ballast restricts the amount of energy output to prevent the bulb from overheating or burning out.
Just as a heart regulates blood flow in the body, a ballast ensures that a light bulb keeps working by stabilizing energy distribution throughout the fixture. The heart distributes blood via arteries in the body to keep it active and alive. Similarly, ballasts have the same responsibility for bulbs but with energy.
An instant start ballast can only be used in a shunted lamp holder. Non shunted lamp holder can be used with the rapid start, pre-heat, program start, and trigger ballasts.
How to tell if a lamp holder is shunted or non-shunted?
In shunted lamp holders, the contacts are connected inside the socket, creating a continuous arc between both electrodes. A non-shunted lamp holder is an opposite. It doesn’t have continuity as there aren’t any connections between the contacts.
To identify the lamp holder type, you need to use a voltage meter to check the contacts for continuity. Continuity can be defined as a complete path of the electrical current in a socket. Set your voltage meter settings to continuity and check. If the meter beeps, lights up, or rings, it means you have a shunted lamp holders.
In some cases, you may also be able to check if a lamp holder is shunted or non-shunted by checking the number of holes in the socket. Non shunted lamp holder usually have four holes, while the shunted usually have two. However, these numbers may vary. So it’s always best to verify the type using a voltage meter.
Final thoughts
We hope now you have understood the difference between shunted and non shunted LED bulbs. Choose as per your electrical needs and reward yourself with a home that is energy efficient!
