Converting Halogen to LED Downlights

Converting Halogen to LED Downlights from Lighting Matters

By: Lighting Matters  27-May-2012
Keywords: Led Lights, Lamps Wholesale & Manufacturing, Led Downlights

Halogen to LED Benefits So you’ve decided to get rid of the nasty halogen down lights in your home and convert them to LED. Great idea! Time to save some money on your electricity bills, not worry about changing over globes, and be thankful that the heat won’t burn your house down. If it were only this easy, the whole world would have changed over already. Halogen to LED First Steps The first step to changing over your halogens to LEDs is understanding what you’ve got at the moment, and what you want as an end result. You will more than likely have either 12V MR16 lamps with a transformer tucked away in the ceiling or a straight 240V supplied GU10 base lamp. 12V MR16 (top) 240V GU10 (bottom) If you have the GU10 lamp base, then there is nothing to worry about. It is a simple globe changeover. A 10W LED GU10 should be able to produce similar amounts of useful light to 50W halogen globes. However if they are MR16, then there are additional steps required to achieve a positive result. Halogen to LED Downlights – Lamp Compatibility MR16 halogen lamps generally run at 12VAC and have transformers attached which convert the 240V mains power down to 12V. Problems can occur with LED downlights when they are connected to existing halogen transformers because of a number of reasons thus making it harder to achieve a positive result. Choosing your voltage – 12V DC or 12V AC/DC or 240V? Cheaper LED downlight globes are often supplied only with a 12V DC input. If this is the case, this LED will not be suitable for use with any halogen transformer and would require a DC only transformer or 12V DC LED driver. 12V MR16 LED downlight globes in the medium to high price range usually come with a rectifier that converters AC to DC to operate the LEDs inside. As such, they should be labelled 12V AC/DC. These LED MR16 globes will operate with some halogen transformers such as the iron cores and a small selection of electronic transformers. Any MR16 LED downlight supplied in a 240V solution should not be purchased for use in Australia. They will not work with any 12V transformer nor be safe to use with a MR16 lamp base. MR16 LED Compatibility with Halogen Transformers Two common types of halogen transformers are the Iron Core (big and heavy) and the Electronic (light and plastic casing). Iron Core transformers rarely have issues which prevent them from driving LEDs correctly. Electronic transformers have a minimum lamp load rating required for the transformer to operate which can cause major headaches for customers wanting to use retrofit globes. If you look at the transformer itself it is often marked with the minimum load required, such as 20-60VA or 10-60VA. (VA means volt-amps, and volts x amps = watts, so in other word 20-60 watts) The problem with using these transformers comes from the low power consumption of the LED downlight globes. There are no retrofit LED MR16 globes which we have encountered that use more than 10W of power to operate so meeting the minimum load is impossible for a single lamp. A 20W halogen meets the minimum load requirement for the transformer to operate effectively because the current is high enough, so no flickering occurs. 12V LED downlights which do not have “intelligent” circuitry in them often do not work properly at all on electronic transformers with minimum loads. Unwanted flickering, low light output, no light output at all, audible buzzing or hum are all common occurrences of this issue. It is far from ideal to the LED light to receive high or frequent current spikes and also far from ideal for the transformer to be switching on and off repeatedly. Quality LED Downlight manufacturers, such as Philips, Brightgreen, Osram and so on have advanced technology inside which mimics the load of a halogen so the electronic transformer and LED downlight operate correctly. The technology varies between lamps and is often patented but the below shows how Philips LED MR16 lamps achieve a positive result. Similarily the Brightgreen DR700 has a virtual load power control system which draws current from the transformer during the entire sinusoidal cycle of the 50/60Hz voltage supply. This allows the electronic transformer to sense that the minimum load requirement is met and it therefore supplies the voltage to the globe. In other words, it’s a far smarter idea to use a more expensive globe with the correct components to operate, than risk the chance of a LED or transformer failing pre-maturely.

Keywords: Downlight Fittings, Interior Lighting - Commercial, Lamps & Lamp Shades, Lamps Wholesale & Manufacturing, Led Bulbs, Led Downlights, Led Lamps, Led Lights, Led Strip