If you are planning to install low voltage lighting fixtures in your home, office or outdoors area, you need to make sure that you have a power supply that can handle the total wattage of your lights. Low voltage lighting fixtures typically come in 12-volt or 24-volt. This means that you need a transformer or a driver to convert the high voltage (120 or 240) to low voltage and provide the right amount of current for your lights.

But how do you calculate what size power supply you need for your low voltage lighting fixtures? Here are some simple steps to follow:

1. Add up the wattage of all your low voltage lighting fixtures. For example, if you have 10 LED lights that use 5 watts each, the total wattage is 10 x 5 = 50 watts.
2. Multiply the total wattage by 1.2 to account for some power loss in the wires and connections. This is called the safety factor. For example, 50 x 1.2 = 60 watts.
3. Choose a power supply that has a higher wattage rating than the result of step 2. For example, if you need 60 watts, you can choose a power supply that has a rating of 75 watts or 100 watts. This will ensure that your power supply is not overloaded and can handle any fluctuations in the power demand.
4. Check the voltage output of your power supply and make sure it matches the voltage input of your low voltage lighting fixtures. For example, if your lights use 12 volts, you need a power supply that outputs 12 volts. If your lights use 24 volts, you need a power supply that outputs 24 volts.
5. Connect your power supply to an outlet that has the same voltage as the input of your power supply. For example, if your power supply has an input of 120 volts, you need to plug it into a standard outlet in North America. If your power supply has an input of 240 volts, you need to plug it into a special outlet or use an adapter in some regions.

By following these steps, you can calculate what size power supply you need for your low voltage lighting fixtures and enjoy the benefits of energy-efficient and versatile lighting in any environment.