Are LED Bulbs dimmable?

When we’re shifting to new technology, we don’t want to throw all our old conveniences away. LEDs are replacing traditional bulbs en masse, but you may have wondered if they work with a dimmer switch. Understandably, you wouldn’t want to lose such a useful functionality for your home and business…

So, are LED bulbs dimmable? Can you dim them with your existing switch? We’re here to answer these questions – and others – surrounding the role dimmers play in the new lighting age.

Short answer – yes, but be careful

Let’s not beat around the eco-friendly bush: LEDs can dim, if you want them to. Only those with a special industry label – which should be easy to spot on the packaging/product info – have that functionality. But they’re getting more common as LED designs flood the market.

The preferable dimmer for this purpose is a variant known as ‘trailing edge’. Regular filament bulbs were often connected to ‘leading edge’ devices, but these can have negative consequences for some LEDs. Dimmers designed for incandescent bulbs require the filament to be part of the controlling circuit, LEDs don’t have a filament and can confuse the operation of the leading edge dimmer resulting in miss-operation and potential failure.

Trailing edge units, on the other hand, generally have a lower minimum wattage load, are designed and generally are tailored for the LEDs they’re be paired with. LEDs require far less power than their counterparts; such characteristics must be considered and designed for. Incompatibility issues may follow and exhibit themselves as:

  • Flickering
  • Abrupt step changes in brightness
  • Limited lighting range
  • Potential damage and failure to the dimmer/lamp(s) over time

You might ask how we prevent any of these from happening. Are LED lights dimmable, and sustainable, all at once? It relies on the lamp/switch combination you go for…

Perfecting your LED system

As we mentioned, dimmers have a set limit to the power they can handle, a maximum level – the wattage rating, but as LEDs operate differently and on a far lower wattage than halogens and incandescent bulbs, the minimum load also counts when fine-tuning your system.

A trailing edge dimmer could have a minimum load of, say, 10W, which corroborates nicely with the base average for LED bulbs. A single trailing edge installation could deliver the right wattage for one 10w LED. However, let’s imagine you’re on a retrofit project, making use of an existing leading edge switch. The lowest limit for that might be 40W… Not ideal for a lone LED lamp, potentially fine for four LEDs hooked up together, all supplied by the same dimmer remembering the incompatibility issues above though.

It’s also worth noting that the LED dimming power supply driver is an essential part of sustainable LED dimming. They convert the power from mains voltage AC to DC suitable for the LED devices, resulting in consistent and even illumination over time. A well designed and constructed dimming power supply increases the compatibility with the vast range of dimmers available.

When we ask ourselves “are LED bulbs dimmable?”, there’s a much larger discussion in the wings, centring on a well-thought-out lighting system. To gain more insight, call the Well-Lit experts, or message us with your thoughts. Ready to start your switchover? Browse our extensive LED catalogue today.

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