What is the difference between 12v and 120v?

12v: known as low voltage, this voltage is acheived by "stepping down", reducing/converting standard 110/120v high voltage into 12v low voltage with the aid of a transformer.

120v: known as high voltage, line voltage, standard voltage or 110v/120v/130v. This is the voltage that comes directly into most homes.

With 12V

• a transformer is required and you must be aware of voltage drop issues
• 12v is the safer option for outdoor lighting, whether it is run near a body of water, under water or in ground.
• 12v usually ends up being cost efficient because you do not have to trench the cable like you would have to for 120v systems (120v requires a conduit and the cable must be trenched)
• 12v is more energy efficient, costing less in running costs
• 12v light bulbs generally last longer than 120v due to the heat generated during operation
• 12v light bulbs are available in a larger variety of wattages, colors and beam spreads options than 120v light bulbs

With 120v

• no transformer is required and no need to worry about voltage drops for landscape lighting applications
• 120v may not be as safe for outdoor lighting, especially in or near a body of water (all junction boxes must be certified waterproof and sealed)
• 120v usually ends up cost more for the initial installation due to need for trenching the 120v cable

Conclusion

With 120v applications, we recommend using a licensed electrical contractor as there is some danger installing 120v systems from electrical shocks. By contrast, 12v systems are utterly safe and can be done by just about anybody provided they are somewhat careful.