For this post, we will discuss the dimmable transformers used in halogen lighting. These are mostly found in under-cabinet applications. The transformer is used to convert the 110 Volt alternating current (the power supply to most North American home wiring) to a 12 volt direct current. The 12 volts applications carry fewer amps and allow smaller wires from bulb to bulb. These smaller wires are easier to manage and conceal in tight spaces.
|48468 - Halogen Lamp Electronic Dimmable Transformer|
From the transformer, there is also a pair of red wires. They will carry the 12 volts to power the halogen bulbs. While the 12 volt DC current has a plus and minus side, the halogen bulbs to not have to tie to a certain side. (NOTE: If you are using this transformer to power 12 volt LED bulbs, you will need to keep the positive and negative sides consistent.) Also, remember the halogen bulbs must be rated for 12 volt circuit.
Most of these applications will have more than one bulb on the transformer, so you will need to keep the circuit organized where the + is on one side and the - is on the other.