Your guide to LED drivers

26 March 2015

Your guide to LED drivers
Your guide to LED drivers

You may have bought or are thinking about buying some LED strip lighting or MR16 fittings or spotlights for your home. Either way you’re here to find out the whats and whys about LED drivers (or transformers). This handy guide will help you make an informed decision and give you the fundamentals you need when buying a driver.

Why do I need an LED driver?

If you’re switching to LED MR16s from halogen MR16s, then LED drivers are pretty important. They’re used to power low voltage (12v) LED bulbs and strip lighting, providing a constant current to make sure they work properly. They’re mainly used for strip lighting, and MR16, MR11 and G4 spotlight bulbs. In some cases your existing (normal) 12v transformer will work. However, this can reduce the lifespan of the bulb.

Which driver do I need for my bulbs?

The driver you need depends on how many bulbs you want it to power multiplied by the wattage. It’s also advised the total wattage of all bulbs combined doesn’t exceed 80% of the transformer’s wattage. So if you choose to power 4 x 4W MR16 bulbs (16W total) from one driver, you’ll need a 20W driver. If you want to power 4 x 6W MR16 bulbs, you’ll need a 30W transformer, and so on.

Which driver do I need for my strip lighting?

The transformer you need for strip lighting depends on multiple factors, such as the length of strip, watts per chip and total wattage. LED strip lighting comes with either small LED chips or larger LED chips, as well as a variety of sizes ranging from 1m to 5m. Small LED strip light chips are marked “3528” and measure 3.5mm x 2.8mm, while large LED strip light chips are marked “5050” and measure 5mm x 5mm. Larger 5050 chips are brighter per metre than small 3528 chips. To calculate the total wattage of the LED strip you wish to power you have to do one of these simple sums: • 60 small LED chips: calculate 5 watts per metre • 120 small LED chips: calculate 10 watts per metre • 60 large LED chips: calculate 15 watts per metre You then need to add another 20% to avoid potential overload on the transformer.

How many transformers do I need?

This is personal preference. Some customers like to have one transformer per fitting or light strip so they can deal with any potential faults easily. It may not always be possible to use one transformer per fitting due to constraints such as space and cost, so keep this in mind when buying. However, many prefer to use one transformer to power a series of bulbs or light strips (maximum five metres on one transformer). As explained above, the transformer you require to do this depends on the combined wattage of the bulbs you’re powering.

How much will an LED driver cost me?

The higher the wattage, the more expensive the transformer, with extra features like dimmable options also adding to the cost. At LED Hut, we charge between £7 to £44.

You can view our full range of LED drivers here.