Replacing Existing 12v Halogen Bulbs To LEDs
All 12v systems require a transformer in order to convert the 230v mains supply to only 12 volts; the required voltage for low voltage light bulbs such as G4s, MR11s and MR16s (G5.3). With the amount of money and energy LEDs can save a household, along with their long lifespan, many people are replacing their existing halogen bulbs with LED equivalents, however there are a couple of things which need to be considered. Here is what you need to know…
There are two different types of transformers: magnetic and electronic. Old style magnetic transformers, also known as wire wound, are fairly simple, using coiled wires around an iron core to convert the power to 12v output. All Lumena transformers work in this way. Electronic transformers have more complications, with some older types, which were generally produced prior to LED bulbs, not being compatible with LEDs. The electronics of the transformer tend to interfere with the electronics of the LED bulbs, thus causing flashing, flickering or even no light output at all. Newer electronic transformers are generally designed with the intent of using with LEDs and therefore work well, as long as the wattage and current type are also correct.
Some LED bulbs will only work with 12v DC power supply. These need to be used with a 12v DC transformer or they will not work correctly, if at all. Some LED bulbs, such as LED G4s, MR11s and MR16s can be run off of both 12v AC and 12v DC which means that either an AC or DC 12v transformer can be used causing no issues at all.
All transformers have a wattage range which must be taken into consideration. If you have a transformer which was previously used with halogen bulbs and you are looking to change these to LED, the likelihood is that the transformer will be too large for the system, expecting a higher amount of current to be running through the system. LEDs use up to 90% less power than halogens, therefore a lower wattage transformer should be used so as not to underload the transformer. If a transformer is underloaded, it was produce a higher voltage output and is likely to cause the LED bulbs to flicker or fail prematurely. Under normal circumstances, it is expected that only the circuit in question will be tripped. If any further lights in the household were to blow, we would advise a second professional opinion in case there is an issue with the electrical wiring.