Table of Contents
An LED strip need a compatible LED Driver (power supply) to convert household alternating current (AC) power to low-voltage direct current (DC) (typically 12V or 24V), which can ensure stable performance and protection.
This guide provides a guidance for driver selection which includes wattage calculations, IP ratings, dimming compatibility, and the difference between Constant Voltage and Constant Current systems which help you make the optimal choice for your setup.
If you want to know more about the power supply parameters, you can read this blog: LED Driver Power Supply Parameters Explain
Constant Voltage vs. Constant Current
In LED lighting, drivers are mainly divided into two categories based on output: Constant Voltage (CV) and Constant Current (CC).
Each type works differently and suits different needs. The first step is to check which one your light fixture requires.
1. Constant Voltage Driver
24V 40W Constant Voltage LED Driver
Input Voltage: AC 220–240V ~ 50/60Hz
Output Voltage: DC 24V (constant)
Output Power: 40W
Output Current: Max 1.7A
Protection Grade: IP20
A Constant Voltage (CV) driver outputs a fixed DC voltage, usually 12V, 24V, or 48V. No matter how many lights you connect (as long as you stay within the power limit), the voltage remains constant. Instead, the current changes naturally based on how many lights are running.
Features: It wires up simply, just like a standard adapter. You can easily connect multiple lights at once, but make sure the voltages match exactly.
2. Constant Current Driver
700mA Constant Current LED Driver
Input Voltage: AC 220–240V ~ 50/60Hz
Output Current: 700mA (constant)
Output Voltage Range: 13–26V DC
Maximum Output Power: 18W
Constant Current (CC) drivers keep the current fixed ( 350mA, 500mA, or 700mA). The voltage changes automatically to match your lights, which give you precise control over brightness and safety. If you need long-distance strips, we recommend constant current LED strip.
In fact, most of LED strips are designed to operate at a fixed voltage. As a result, most LED drivers available on the market for strip are Constant Voltage (CV) drivers. The difference between constant voltage LED strips and constant current LED strips can be found in this blog: Constant Current LED Strip VS Constant Voltage LED Strip
Voltage Must Match: 12V, 24V, or 48V
The voltage of your power supply must exactly match the voltage of your LED strip.
- If your strip is 12V, you need a 12V driver.
- If your strip is 24V, you need a 24V driver.
- A 12V strip fails immediately on a 24V power supply. A 24V strip glows dimly or stops working on a 12V power supply.
Understand led strips with different voltage: 48v vs 12v vs 24v vs 36v LED Strip
How to Calculate Wattage
- Find the power consumption (W/ft or W/m) on the package.
- Determine the total length of led strips.
- Multiply watts by total length to calculate total load: 8.4 W/m × 5m = 42 W
- Divide the total load by 0.8 to find the minimum driver size needed.
42 W ÷ 0.8 = 52.5 W → Choose a 60W or larger driver
- If your calculated load is 40W, buy a 50W supply.
- If your calculated load is 75W, buy a 100W supply.
- If your calculated load is 150W, buy a 200W supply (or use two 100W supplies).
Never round down! When in doubt, always size up. This guide tells you how to avoid power overload risks in LED projects: How to Calculate the LED Power Supply for LED Strip
Application Environment: Indoor vs. Outdoor
Your installation location determines the required power supply safety rating. Choose a waterproof supply for outdoors and a standard one for indoors.
Characteristics: Most of these come in plastic or as a metal frame with gaps. They are not water-resistant.
Installation Note: Even inside, US rules often say to hide these in a box or cabinet. This stops people from touching them by accident.
Outdoor / Wet Locations (IP65, IP67, IP68)
Characteristics: Fully sealed. They are placed in a metal box with holes and are packed with hard glue to prevent water ingress.
IP65: Safe from splashes. Use it under a roof so rain stays away.
IP67/IP68: Fully waterproof. You can put it under water. It is safe for direct rain, snow, or the garden.
Dimmable vs. Non-Dimmable Power Supply
According to the signal type, dimmable power supplies are mainly classified into the following three categories:
1. TRIAC Dimming
Also known as phase cut dimming, this is the most traditional and widely used method.
It adjusts brightness by cutting part of the AC waveform and is typically used with wall dimmer switches.
- Advantages: low cost, good compatibility
- Applications: residential lighting, retrofit projects
2. 0-10V Dimming
Uses an analog voltage signal from 0 to 10V to control brightness.
Higher voltage means higher brightness.
- Advantages: stable, strong anti interference performance
- Applications: commercial lighting, offices, projects
3. DALI Dimming
A digital control system that allows individual addressing of each light.
Each fixture can be controlled separately.
- Advantages: highly intelligent, supports grouping and scene control
- Applications: smart buildings, commercial spaces
Brand and Budget Recommendations
In fact, over 80% of LED lighting issues come from the driver, not the LED chips. So it is quite important to choose a right power supply.
A good quality driver usually means:
It uses high quality components for a longer lifespan and includes full protection features such as overvoltage, overcurrent, short circuit, and overheating protection.
It also provides reliable power output with sufficient margin and meets relevant safety certifications and standards.
Simply put: a better driver = longer lifespan + safer operation.
Brand Comparison Overview
| Tier | Representative Brands/Series | Design Lifespan | Warranty Period | UL Certification | Typical Applications |
|---|---|---|---|---|---|
| Good | White-label / Entry-level | 10,000–20,000h | 1 year | Usually none | Short-term, temporary, non-critical |
| Better | Mean Well APV/LPV/NPF | 30,000–50,000h | 2–3 years | UL/ETL | Residential mainstream, basic commercial |
| Best | Mean Well HLG/ELG/XLG | 50,000h+ | 5 years | UL/ETL | Architectural lighting, high-end projects |
| Best | Philips / Tridonic | 50,000h+ | 5–7 years | UL/cUL/CEC | Smart lighting, museum-grade |
