Dimmable LED: which dimmer do you need?

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1) First: is your lamp dimmable?

Always confirm the LED lamp/driver is dimmable. If it’s not marked dimmable in the specs, dimming will usually cause issues.

Tip: for fixtures with integrated LEDs (downlights/panels), the driver is key: it must be dimmable and compatible with the dimmer type.

2) Which dimmer do you need? (trailing / leading / universal)

In practice, you’ll see three common options:

• Trailing-edge (RC) – often best for LED: stable, quiet, smooth dimming.
• Leading-edge (RL) – older technology (halogen); can work but may buzz or flicker with LEDs.
• Universal (RL+RC) – useful if you’re unsure or have mixed loads.

Rule of thumb: for LEDs, prefer RC or a quality universal LED dimmer.

3) Wattage calculation (most common cause of issues)

Add up the wattage of all connected lamps. Then check if your dimmer supports that minimum and maximum load. LEDs use little power, so older dimmers often won’t reach their minimum.

Example: 6 × 5W LED = 30W total. Choose a dimmer rated for that LED range (e.g., 3–100W LED).

4) Common problems + quick fixes

5) Quick selection (30 seconds)

• Step 1: Is the lamp/driver dimmable? (yes/no)
• Step 2: Add up total wattage (W).
• Step 3: Prefer RC or universal (LED-rated).
• Step 4: Check min/max range fits your total W.
• Step 5: Test: flicker or buzz? → different dimmer/driver or bypass.

FAQ

Summary

• First confirm your LED/driver is dimmable.
• For LEDs, prefer RC or a quality universal LED dimmer.
• Add wattage and ensure you’re within the dimmer’s min/max range.