LED Supply: Choosing the Right LED power supply


Do you need a device that provides power to your LED projects? A LEDs power supply can do the job! It transforms energy to either a voltage or current for the LED product. About LED supply, LEDs have revolutionized lighting technology by the longevity of bulb life compared to incandescent bulbs.

While searching for the proper LEDs power supply can be a confusing task. That’s why we’ve got you covered on this topic.

Sit back, relax, and read on!

What is an LED Power Supply?

LED Power Supply

A LEDs power supply delivers a regulated constant voltage to LEDs, allowing them to operate and perform at a high level. The device works like a fluorescent lamp’s magnetic ballast or a low-voltage bulb transformer.

LED light modules connect a series of LEDs, forming clusters of string configurations. These light modules require a constant-voltage power supply if they have a constant-current driver in the assembly. Generally, DC-DC and AC-DC converters regulate the input voltage into a constant voltage.

It’s essential to determine whether the output voltage provides a constant voltage or constant current required by the product receiving the power.

Different Types of an LED Power Supply

LED Power Supply
  • Plug-in – The plug-in LED power supplies support 12VDC and 24VDC output. All you need to do is plug a LED transformer into a 120VAC power socket to power up the 12-24VDC LED lights.
  • Indoor –An indoor LEDs power supply operates in a dry environment. Some can plug into a wall socket, while others can be hard-wired to an AC source.
  • Waterproof – A waterproof LEDs power supply protects your device from water damage. There are a variety of different types designed for the outdoors.
  • Dimmable – A dimmable LED power supplies allow you to adjust the brightness of a 12VDC or 24VDC LED light using a low magnetic dimmer. This device is compatible with different low voltage magnetic dimmers, making it ideal for dimming LED lights in large-scale applications. 

How To Choose an LED Power Supply


The LED power supplies should have 1.2 times the LED lights’ total wattage. Doing so gives you a 20% cushion, which keeps your power supply safe from surges or other issues.


It’s essential to ensure that the output voltage works with the LED’s voltage if you’re replacing a power supply or developing a LEDs fixture. LEDs containing built-in current regulators indicate the recommended input voltage. You can also use high-power LEDs with constant-current drivers requiring a DC voltage input.

Your power supply should also be able to withstand the input power. You should make sure it has low-line AC power or high-line AC power. Most power supplies are full-range rated, but it would be helpful to know the AC input while ensuring the power supply can handle it.

The application environment

application environment

These three questions help determine the application environment of the LED power supply.

i) Is it for indoor or outdoor use? 

ii) Does the LED power supply need waterproof or a specific IP level? 

iii) Does it use conduction cooling or convection cooling?

You need to consider its operational environment to determine the different LED power supply types. Your LED power supply’s IP rating should be 65 or 67 if you install LED strip lights in a wet or humid area.

An LED power supply’s ingress protection (IP) level determines how effectively the enclosures keep the device protected against dust and moisture. An IP rating has two digits. The first digit ranges from 0-6, with 6 keeping dust out. The second digit ranges from 0-9, with 9 meaning that water cannot penetrate the power supply.

Using your LED power supply in specific environmental and temperature factors can play a vital role in its operational life. Generally, it runs best in a particular temperature range, as indicated in the specifications. It’s also bad practice to put the power supply in a warm area and a tiny enclosure, where heat can quickly build up and damage the unit. If it overheats for a long time, it will stop functioning. Installing a heat sink or fans can help prevent this from happening.

Dimmable or non-dimmable LED power supply.

Dimmable LEDs allow you to adjust the brightness. For this to work, your LED power supply must have dimming capabilities. A power supply specifies whether or not a power source is dimmable or non-dimmable. There are two different control types, PWM Dimming and TRIAC Dimming.

  • PWM Dimming

All types of power supplies use pulse-width modulation (PWM) dimming. Positioned between the power supply and LED lights, these dimmers work by pulsing LED lights at high frequencies. This makes them appear like a steady, dimmed light.

  • TRIAC Dimming

Triode for Alternating Current (TRIAC) is a high-speed switch that controls how much power flows to a bulb. A TRIAC dimmable power supply requires you to use this dimmer since it does not directly dim LED lights.

UL listed or other safety certifications.

An Underwriters’ Laboratories (UL) listed LED power supply provides more protection than one that isn’t UL listed. A UL-listed power supply makes it safe for industrial, commercial, and residential applications. An LED power supply must be UL listed for renovation projects.

Additionally, an LED power supply has two standards: Class 2 and Class II. These improve its safety during operational use and installation. A high-quality LED power supply allows the LED lighting system to run steadily and efficiently. This can extend the light fixture’s lifetime, save energy, and reduce maintenance costs.

Determine the connection method

Determine the connection method

Usually, a power supply comes bundled with a power connector, which measures 5.5 mm x 2.1 mm. The connector may not function with LED strip plugs if it’s 5.5 mm x 2.5 mm.

Does the LED strip reel plug have a DC plug? If so, then you need an adapter. It connects the power connector from the power supply to the LED strip. Next, you must wire the loose ends into the adapter, which connects to the power supply.

The proper size to use

Typically, the power supply’s capacity is de-rated by 20%. This is to ensure it lasts longer. When selecting a power supply, divide the lights’ total watt consumption by 80%. The final number determines if the unit is safe. If a power supply’s total wattage is 100 watts, divide that number by .8, resulting in 125 watts. Then, you choose a 150-watt power supply.

How to connect LED strip lights to the power supply

LED strip lights

To connect an LED strip light to a 12V LED power supply, plug the V+ to V+ and V- to V-. These polarities must match. You can also place an LED dimmer between the LED strip and the power supply to adjust the brightness.

To get a LED strip to work on a 24V power supply, separate a 12V LED strip into two segments. Then connect the copper pads in a series so that both wattages add up to 24V, allowing it to match with the power supply.

Qualitative LED power supply.

  • Reliable

Lighting products should function over a long period of operational use. For example, installing an LED street lamp’s driving power takes place at a high altitude. This makes it difficult to perform maintenance, which can be expensive. However, the maintenance cost is significantly lessened if it has high reliability.

  • Efficiency

LEDs require high efficiency in power supplies since they’re energy-efficient. If the power supply’s efficiency is higher, it consumes less power.

  • Power factor

A high power factor significantly reduces the power supply’s load and loss and keeps the lighting products running smoothly. However, it requires larger generators, transformers, and transmission lines due to the high reactive power.

LED power supply calculator

Calculating the total wattage for a LED power supply to run a LED light strip is straightforward. All you need to do is find the total wattage of your lighting and multiply it by 1.2.

For example, if you have five LED strip lights at 4 watts each, then the sum of the wattage is 20.

Next, multiply that number by 1.2.

20 x 1.2 = 24.

This shows you need a 24-watt or higher power supply to deliver power to the LED lights.


Q1: What power supply requires an LED strip?

The wattage of LEDs strip lighting should be 20% less than that of a LEDs power supply. If you have an 80W LED strip light, then 96W power supplies are needed.

Q2: Can a LED driver be used as a power supply?

Yes, but they are current sources, not voltage sources. The LED driver should provide a constant voltage to use as a power supply.

Q3: What is the difference between a LED driver and a power supply?

Whereas LED drivers deliver a constant-current output, an LED power supply gives a regulated constant voltage to LEDs.

Ending thoughts:

Overall, a LEDs power supply is the correct device to provide power to your lighting project. You should be aware of the temperature and environment so that it doesn’t get too hot and fail. An LED power supply supports PWM Dimming or TRIAC Dimming to adjust the brightness levels of your LED. Ensuring the power supply’s capacity is de-rated by 20% helps to keep it safe from damage. 

A LEDs power supply is the way to go when powering up your LED lights.

Do you have any questions regarding an LED power supply? Feel free to contact us!

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