The Short Answer
LED lights run off 12V direct current (DC) while halogen lighting transformers generally provide alternating current (AC). This causes the LED light to flicker and can damage your globe. You will need to either replace your transformer with an LED transformer that provides DC or buy an LED globe that has been designed to work on halogen or AC transformers.
The Long Answer
Electronic transformers and Iron Core transformers commonly used by halogen lights cannot provide a smooth current output to LED's and instead output tiny bursts of current causing LED's to flicker. These tiny bursts of current not only causes flicker but can actually result in permanent damage to the LED's. Sometimes you may not notice the flicker because it is too faint, nevertheless, the halogen transformer will still cause damage to your LED and reduce its lifetime severely. Another isse is halogen transformers generally have a minimum load of 30W. Using a 7W LED with such a transformer would cause it to restart constantantly as it struggles to detect the low load of the LED light.
Types of flickering
This flicker may not occur instantly and may only be noticeable after a few minutes. The flicker can also be very slight and you may not even notice it until you watch the light carefully on the floor. In some cases the flicker can be quite distracting making the LED downlight unusable.
The easiest way to avoid this issue is by purchasing LED lights which are designed to be compatible with AC / halogen transformers. The Osram and Philips MR16 LED downlights we sell work on 99.9% of transfomers. If you have issues with them, you can return them for a full refund no questions asked.
If you have already purchased LED lights and find them unsuitable for your existing setup, you can purchase an LED transformer ($9) as a replacement for your existing halogen transformers.For new downlight installations or renovations, we recommend using LED downlight kits. These are far more efficient and include everything needed for a downlight installation i.e. LED downlight, fixture, transformer & plug
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