Our lamp holders are divided into T8 G13 lampholder and T5 G5 lampholder, and these products are also called light socket, lamp socket and lamp base. Meanwhile, lamp holders have shunted lampholder and non-shunted lampholder. Well, how do I tell if my lamp sockets are shunted or non-shunted ?

Honestly, this is quite an important question to answer for linear fluorescent or LED light fixtures. As it will ensure you get maximum life out of your lighting and avoid dangerous fire hazards. Using the wrong type can not only cause an electrical short, resulting in a fire hazard –– melting the sockets or tubes, but also can almost always shortens the life of the lamp.

But lots of our buyers have less knowledge of shunted and non-shunted sockets. Actually, there's an easy way to know the difference between shunted and non-shunted sockets and when you need which.

When it comes to the shunted lamp holder, then just think as "joined" or "connected". Shunted sockets have contacts that are joined or connected. This provides a single track for the electrical current to travel from the ballast, through the tombstone, or socket, and to the lamp's pins. While, the non-shunted sockets have separate contacts, or points of entry for the wires, creating two tracks for the electrical current to travel. Non-shunted sockets have contacts that are not joined or connected, two different signals can be sent to the pins independently.

The following diagram visually demonstrates the difference, you'll most often see between the two types of sockets.

However, the safest and the most certain way to tell what kind of sockets you have is surely to use a voltage meter. Most voltage meters will either light up or ring or beep if the electrical contacts are connected(or shunted).