When it comes to fluorescent lighting sockets, you have two basic types of wiring configurations. Some sockets are shunted while others are non shunted sockets. Unless you have specific knowledge on this kind of lighting, it can be confusing. Here is important information on the differences and similarities.
What Does Shunted Mean?
Shunt means to divert or switch from one area to another. For example, when they switch railcars from one track to another track, this is called shunting. A surgical shunt is installed in an area to drain or divert fluid from a specific body region.
In electrical terms, shunting is a little different. For example, suppose you have two leads or connections. To get power to both connections, you can run separate wires or conductors to each one (non shunted sockets). You can also run one wire to a connection and tap into it and run a lead to the other connection. This is known as shunting for electrical sockets.
Testing
It is not hard to determine if a socket is shunted or not. All you need is a digital voltmeter with a continuity checking feature or an analog meter set to “ohms” for resistance checking. Touch the leads across both socket connections. With the digital meter set to continuity, you hear a buzzer with a closed circuit. The analog meter needle moves all the way to the right when there is a closed circuit, and this indicates a shunted socket. Non shunted sockets show an open circuit (nothing) when checking continuity.
Uses
For fluorescent lighting with instant start ballasts, you need non shunted sockets. Most other types of sockets are un-shunted types, and this includes trigger ballasts, rapid start, and dimmable bulbs. If you are unsure which sockets to use, contact your fluorescent and LED lighting specialists.