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A guide to LED power supplies (LED Drivers)

An LED power supply (also called an LED driver or LED transformer) converts your mains AC electricity into the DC power that LEDs need to operate.

Think of it like this: Your home runs on AC power, but LEDs need DC power. The power supply is the translator between them. Choose the wrong one, and your lights won't work - or worse, they'll be damaged.

Already know what you need? Browse our full range of LED drivers →

This guide will help you understand the key differences so you can choose the right driver from our power supply collection with confidence.


⚡ Choosing the Right Voltage (5V vs 12V vs 24V)

⚠️ CRITICAL: Your LEDs will be marked with their voltage (5V, 12V or 24V). Your driver MUST match this exactly. Too high a voltage (e.g. a 24V driver on 12V LEDs) can burn out the LEDs and is a potential fire risk. Too low a voltage (e.g. a 12V driver on 24V LEDs) won't cause damage, but your LEDs simply won't light up.

When to use each voltage:

🔵 5V Drivers

Best for: Small, USB-powered projects

  • TV backlighting (up to 2m)
  • Display cabinet accents
  • PC case lighting
  • Battery-powered projects

Real Example: 2m LED strip behind a TV = 5V 30W driver needed

→ Browse 5V Drivers

🔵 12V Drivers (MOST COMMON)

Best for: Most home installations up to 5m

  • Kitchen cabinet lighting
  • Bedroom & living room strips
  • Bathroom mirrors (with IP rating)
  • Garden lighting (with weatherproofing)

Real Example: 5m kitchen cabinet strip = 12V driver at 60-100W needed

→ Browse 12V Drivers

🔵 24V Drivers

Best for: Long runs over 5m & commercial projects

  • Shop displays & retail lighting
  • Office installations
  • Architectural features
  • Any run over 10m

Real Example: 10m retail display = 24V driver at 150W+ needed

→ Browse 24V Drivers


🔢 Calculating How Much Power You Need

Simple 4-Step Formula:

  1. Find your LED's watts per metre (it's on the product page)
  2. Multiply by your total length (in metres)
  3. Add 20% safety margin (multiply by 1.2)
  4. Round up to the next available size

📐 Real Calculation Example:

Your LED strip: 14.4W per metre
Your length: 5 metres

5m × 14.4W = 72W
72W × 1.2 (safety margin) = 86.4W
→ Choose a 100W driver

❌ COMMON MISTAKE: Don't run a 60W supply for 60W of LEDs! It'll overheat and fail within months. Always add that 20% buffer.


🎛️ Understanding Dimmable Options

Not all dimmable drivers work the same way. Here's how the three main types compare, so you can pick the right one from our dimmable range:

TRIAC Dimmable

Works with: Standard wall dimmers

Best for: Home installations

  • ✅ Uses existing dimmer switches
  • ✅ Simple to install
  • ✅ Affordable option
  • ❌ Single zone only

→ View TRIAC Dimmable PSUs

DALI Dimmable

Works with: Digital control systems

Best for: Commercial buildings

  • ✅ Control 64 zones individually
  • ✅ Create lighting scenes
  • ✅ 0.1% to 100% dimming
  • ❌ Requires DALI controller

→ View DALI PSUs

0-10V Dimmable

Works with: Low voltage controllers

Best for: Simple commercial

  • ✅ Reliable & simple
  • ✅ Works with sensors
  • ✅ Good for retrofits
  • ❌ Requires control wiring

→ View 0-10V PSUs

💡 PRO TIP: Many of our drivers accept ALL THREE dimming types (TRIAC, DALI, and 0-10V). Perfect if you're not sure what you'll use yet!


🔌 Plug-in vs Hardwired – Which Do You Need?

Plug-in Drivers

Perfect when:

  • ✅ No electrician needed
  • ✅ Adding to furniture
  • ✅ Temporary installation
  • ✅ Under 100W total

Includes:

  • 1.8m cable
  • 2.1mm DC plug
  • Safety protections

→ Shop Plug-in PSUs

Hardwired Drivers

Best when:

  • ✅ Permanent installation
  • ✅ Over 100W needed
  • ✅ Multiple LED runs
  • ✅ Hidden installation

Options:

  • IP20 (indoor)
  • IP65 (bathroom/outdoor)
  • IP67 (fully weatherproof)

→ Shop MEAN WELL Drivers


⚡ Quick Driver Selector

Answer these 4 questions, then head to our driver collection to find your match:

30-Second Selector Tool

1️⃣ What's your LED voltage?

→ Check your LED product (5V / 12V / 24V)

2️⃣ How many watts do you need?

→ Length (m) × watts/m × 1.2 = _____W

3️⃣ Where's it being installed?

→ Indoor dry = IP20 | Bathroom = IP44 | Outdoor = IP65+

4️⃣ Need dimming?

→ No / Wall dimmer (TRIAC) / Smart system (DALI)

Common Setups - Quick Reference

Project Typical Driver Needed Shop Link
3m Kitchen Cabinets 12V 60W Plug-in View Options →
5m Living Room 12V 100W TRIAC Dimmable View Options →
10m Garden Path 24V 150W IP67 View Options →
Bathroom Mirror 12V 30W IP44 View Options →
Shop Display 24V 200W DALI View Options →

❌ 5 Expensive Mistakes to Avoid

1. Wrong Voltage = Damaged LEDs or No Light

A driver voltage higher than your LEDs (e.g. 24V into 12V strips) can burn them out and poses a fire risk. A driver voltage lower than your LEDs won't cause damage, but they simply won't light up.

✅ Solution: Always match your driver voltage to your LED voltage exactly.

2. No Safety Margin = Early Failure

Running at 100% capacity overheats the PSU. Lifespan drops from 5 years to 6 months.

✅ Solution: Always add 20% headroom to your calculations.

3. Wrong IP Rating = Water Damage

Indoor PSU in bathroom = moisture failure within weeks.

✅ Solution: IP44+ for bathrooms, IP65+ for outdoors.

4. Incompatible Dimmer = Flickering

TRIAC dimmer with non-TRIAC driver = flickering, buzzing, or no dimming.

✅ Solution: Match dimmer type to driver type.

5. Voltage Drop on Long Runs

12V over 10m = dim LEDs at the end.

✅ Solution: Use 24V for runs over 5m, or add power injection points.


🔧 Professional Installation Tips

Installation Best Practices

📍 Location & Ventilation:

  • Keep 10cm clearance around PSU for cooling
  • Mount where accessible for maintenance
  • Never bury in insulation
  • Check ambient temperature rating

⚡ Wiring Safety:

  • Use 1.5mm² cable minimum for long runs
  • Keep AC and DC cables separated
  • Add inline fuses for protection
  • Label everything for future reference

📋 Planning Ahead:

  • Zone circuits for easier control
  • Include 30% spare capacity for additions
  • Document your installation
  • Keep spare fuses/connectors

✅ Ready to Choose Your Driver?

Browse Our Complete Range

Professional-grade LED drivers with up to 7-year warranties

🤔 Still Not Sure?

Our technical team provides FREE consultation for any project

Email us: sales@weloveleds.co.uk

Include your project details and we'll recommend the perfect driver within 24 hours


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