Choosing the correct power supply for your LED projectUpdated 10 days ago

Selecting the appropriate power supply is crucial to the success of your LED lighting project. The right power supply ensures your LED strips or modules operate performantly and have a long lifespan. This guide will help you understand how to choose a power supply that matches the needs of your installation.

If you just want quick and easy way filter our offerings down to a selection of suitable options, try our driver recommender.

Note: This guide deals with typical, "constant voltage" LED strips and constant voltage power supplies. If you require a constant current supply or are unsure, please contact us for guidance.

Calculating your power requirements

To determine what wattage power supply you need, you will need to calculate the total power consumption of your installation.

This is pretty similar between strips and modules, but we've detailed the steps for both to make it simpler.

Note that the calculator in our driver recommender tool can be used for these calculations, even if you don't use the recommendations.

Calculating LED strip power consumption

To calculate the total power consumption of your LED strip:

• Find the power consumption of your LED strip. On our site, this is listed in watts per meter in the 'General specifications' section of the description on the product page.
• Multiply the power consumption by the total length in meters of LED strip you will use.
• If you are powering multiple different models of LED strip from the same power supply, calculate the total consumption of each model and add those totals together to get the combined total of all the strips.

The basic formula for the above looks like this:
[LED strip wattage] x [LED strip length]

It's fine to round the result to the nearest watt for convenience.

You can use power consumption in W/ft or length in feet – just remember to convert units as needed. Tip: If you enter the formula into Google, it will calculate it and handle unit conversion for you. E.g., searching "8.4 W/m * 26 ft" gives the result "66.56832 watts".

Calculating LED module power consumption

The above can be applied to LED modules as well, just using the wattage per module instead of wattage per meter and number of modules instead of length.

To calculate the total power consumption of your LED modules:

• Find the power consumption of your LED modules. On our site, this is listed in watts per module in the 'General specifications' section of the description on the product page.
• Multiply the power consumption by the total number of LED modules you will use.
• If you are powering multiple different models of LED modules from the same power supply, calculate the total consumption of each model and add those totals together to get the combined total of all the modules.

The basic formula for the above looks like this:
[LED module wattage] x [Number of LED modules]

It's fine to round the result to the nearest watt for convenience.

Calculating the total power consumption

To calculate the total power consumption of your installation, take the consumption of your LEDs and add the requirements of any controllers or other devices you will be powering from the power supply. This gives you the total power consumption you need to support.

Most controllers and similar on our site have their power requirements listed in the 'General specifications' section of the description on the product page; and if not, it should be in the spec sheet. They usually use an insignificant amount of power themselves (less than 1W), but it's always worth checking just in case, especially if your LEDs consumption is very low and even a little bit more wattage will affect the size of power supply you need.

Choosing the right power supply

Allow some headroom in wattage

Choose a power supply that can provide at least 20% more power than your total calculated consumption. This provides some headroom to allow for heating, current surges, etc., which will help prevent the power supply failing in edge cases and will generally improve its lifespan.

For example, if you calculate your consumption is 130W don't get a 130W or 140W supply, get a supply with at least 130W * 120% = 156W of output power.

Select the correct voltage

Ensure the voltage of the power supply matches the voltage of your LED strips or modules. Common voltages are 12V or 24V. The voltage of a strip is usually printed on the strip by the solder pads. For modules, it's usually labeled on them; either embossed in the housing or cover, or printed internally and visible through the cover.

Consider the installation environment

Consider the environment where the power supply will be installed. If it's an area prone to moisture or dust, look for a power supply with an appropriate ingress protection (IP) rating.

Quality and safety tips

• Opt for a power supply with short circuit protection to safeguard your LED strips and power supply.
• Choose a power supply from a reputable manufacturer to avoid quality issues.
• Ensure the power supply you select has the necessary certifications for your project (e.g., UL, CE, RoHS).

All the power supplies offered on our site are great options!

Practical tips

Consolidating power supplies

If your project has multiple sections of LED strip or modules, consider whether you want a separate power supply for each section or a single larger power supply for everything. Separate power supplies can be easier to manage and replace but using a single power supply reduces complexity.

This is especially important if you do not use any LED controllers, as then the LEDs will be controlled via the power supply. If you need to be able to control the sections individually, you will need multiple power supplies.

Installation location

Install the power supply in an accessible location where it can be easily reached for maintenance or replacement.

Prefer installing it in a well-ventilated area to prevent overheating. For smaller installations, such as under-cabinet lighting, installing the driver inside a cabinet or similar is acceptable. For high-power installations they should be in the open air, or actively cooled if enclosed.

Future expansion

If you plan to expand your LED project in the future, consider choosing a power supply that can accommodate the additional load to avoid the hassle and expense of upgrading it later.

Conclusion

Choosing the correct power supply is a vital step in your LED project. By understanding your project's total power consumption, matching the voltage, considering the installation environment, and focusing on quality and safety, you can select a power supply that ensures the longevity and performance of your LED lighting. Remember to reference the 'General specifications' on our product pages for accurate power specifications and plan with a forward-thinking approach for a successful LED installation.