Line Voltage vs. Low Voltage
Check out the following lighting facts to understand the differences between
line-voltage and low-voltage fixtures and bulbs.
Line Voltage vs. Low Voltage
Line voltage is the standard voltage—120 volts—that’s found in outlets and junction boxes in the United States and Canada. For this, line-voltage fixtures are basically plug-and-play. Low-voltage lighting typically uses 12 or 24 volts and requires a transformer to lower the line voltage from 120 volts to avoid immediately burning out the low-voltage bulb.
The transformer for low-voltage lighting is either built into the fixture or located remotely. The wattage rating of a transformer should be the same or higher than the combined wattage of the lighting system. Transformers typically require a minimum combined wattage in order to operate the lighting system effectively, and without flickering or humming.
The benefits of line voltage include lower-cost fixtures and light bulbs and easier installation. Dimmers for line-voltage lighting are also less expensive than those used with low-voltage lighting. Although the initial cost is lower, operating costs are typically higher for line-voltage lights, unless they're installed in low-use areas, in which case the operating cost difference will be negligible.
While low-voltage light fixtures, bulbs and dimmers are considerably more expensive due to the need for a transformer, the operating costs over time are typically lower than line-voltage operation if the lighting system is frequently used.
Quality of Light
The light produced by low-voltage bulbs is sharper and looks more natural than higher voltage bulbs, which produce warm light that's more diffused. While it's difficult to focus the beam of a high-voltage bulb that tends to scatter light, low-voltage bulbs offer a high degree of optical control using just the bulb's reflector. That's because the filament in a low-volt lamp is smaller than that of a standard lamp, and most of the lumens are focused in the beam. As a result, less light is diffused.
Energy Efficiency & Associated Costs
While a low-voltage bulb, such as a 50-watt MR16, doesn't use less electricity than a standard line-voltage bulb with the same wattage, the former will provide nearly 100 watts' worth of illumination for the same power consumption. And light is more effectively concentrated where it's needed, which can reduce the number of fixtures needed for a particular lighting scheme.
Low-voltage bulbs tend to last longer, too. While a standard household bulb will last around 750 hours, a standard MR16 lasts 6,000 hours. Low-voltage lamps also break less frequently than high-voltage lamps because they're made to be more shock and vibration resistant.
Applications for Line + Low Voltage
Line-voltage lighting is best for applications that require more diffused ambient light. Best of all, you just hook it up (or plug it in) and go.
Low-voltage lighting can be used in the same spaces and for the same purposes as line-voltage lighting, but for contemporary lighting schemes, low-voltage lighting is ultimately more practical, safer and less expensive to operate. Low-voltage lighting is available in a wide range of styles, including recessed can lights, track lighting, rail lighting systems, low voltage pendant lighting, display lights and suspended cable lighting.
Because more modern lighting options are available with low-voltage lighting in terms of fixtures, lenses, bulbs and beams, low-voltage lighting is ideal for illuminating artwork, creating a desired ambiance and lighting work spaces.
The Bottom Line of Line Voltage vs. Low Voltage
Both line-voltage and low-voltage lighting systems have advantages. But choosing one over the other largely comes down to the ease of installation and long-term operation and the costs associated with both. Line-voltage lighting is typically more expensive to operate in the long run, but it's less expensive to buy and easier to install. Low-voltage lighting is more expensive to buy and install, but it's typically less expensive to operate over time.