Low Voltage Transformer Applications & Features
Low voltage lighting systems require less voltage to operate than the typical line voltage supplies. If your wall receptacle outputs 120 volts, that’s far more than your 12 or 24 volt light fixture will need. Low voltage transformers step down the voltage to match your light fixture requirements. Without these converters, the electricity coming from your wall receptacle would be far too powerful to operate your lights and would burn them out.
Electronic vs. Magnetic
Electronic transformers are smaller in size and provide a maximum of 300 watts of power which makes them a good choice for regulating voltage in smaller lighting applications like kitchens, bathrooms or entertainment rooms. Since magnetic transformers are generally larger and can provide up to 1200 watts of power, they are often ideal for big projects like extensive outdoor landscape lighting. Both types have models that can be hard-wired or plugged directly into an outlet and offer single circuit and multi circuit capabilities.
Choosing the Right Low Voltage Transformer
Electronic? Magnetic? Multi-tap? Multi-circuit? Universal? With all of the choices available, sometimes choosing the right one can seem like a daunting task. For an easy 4-step guide to figuring out exactly what kind of transformer you need, see How to Choose a Low Voltage Transformer in 4 Steps.
The best resource for electrical wiring is a licensed electrician, but with the right tools and information, it is possible for a homeowner to wire their own low voltage transformer. Make sure that the input wires are connected to the power line using wire nuts, and that the output wires are connected to the low-voltage light source using wire “terminal blocks” of appropriate size (for solid contact). Low voltage halogen or xenon lighting systems carry relatively large currents so all of the connections must be very tight to prevent arcing (a possible fire hazard) within those connections. That’s why we recommend that you use terminal blocks. If a transformer is equipped with wires, then you will usually find that the thicker wires are on the low voltage side and the thinner wires are on the line voltage side.
Here are a few simple things to look for when you suspect that your transformer isn’t working correctly:
- Please make certain that the input wires (primary side) are connected to the power line (120 volts or 277 volts) and that the output wires (secondary side) are connected to the low voltage light source (12 volts or 24 volts). Most failures occur as a result of reverse or improper wiring.
- Check the filament (the tiny string-like wire inside the lamp) to see if it is burned out. (Remember the glass envelope of many halogen light bulbs should not be touched by bare hands because the natural oil from your hands will cause the lamp to burn out prematurely.)
- Check the connections of the lamp with the socket by moving the lamp inside the lamp holder.
- Check the voltage with a voltmeter. (Since most voltmeters give misleading readings when applied to high-frequency currents, the voltage on a transformer can be measured only by using a “true RMS” voltmeter with a sufficient range.)