Replacing 12V Halogen MR16s with LEDs

Thinking about making the change from Low Voltage Halogen to LEDs?
 
With rumours starting to circulate about the possible ban on low voltage Halogen MR16s by the European Union, we need to start looking for suitable LED alternatives. There is a lot of confusion and misleading information about how to go about this change regarding transformer compatibility. Here we will try to explain how to make this change over and what is needed to make it as simple and hassle free as possible.
 
The first thing you need to do is correctly identify the wattage of the bulb and the rating (VA) of the transformer that you are currently using. When using standard Halogen bulbs the transformer rating will tell you the maximum and minimum loading (Watts), which in turn, tells you how many and what wattage bulbs you could successfully install. When fitting an LED however, the bulb should be considered by its Halogen Equivalent Wattage not its Rated Wattage, which only tells you the power or electricity consumed.
 
Below are some examples of Light Output compared to Power Consumption
Philips 20w Equivalent MR16 GE 35w Equivalent MR16 Crompton 50w Equivalent MR16
Philips 4W LED MR16 GE 7W LED MR16 Crompton 5W LED MR16
Examples of Single and Multiple LED Transformer Loadings
 
Example 1  
A room has 4 downlights using 50w Halogen bulbs each has its own transformer all rated at 60VA. You could successfully replace the Halogens with the Crompton 5w LED MR16 which gives out light equivalent to the 50w Halogen bulb. So to summarise - Total equivalent wattage equals transformer rating required. Individual MR16 LED Transformer Loading Example
Example 2  
A room has 6 downlights using 35w Halogen bulbs run from 1 central transformer rated at 225VA. You could successfully replace the Halogens with the GE 7w LED MR16 which gives out light equivalent to the 35w Halogen bulb. So to summarise - Total equivalent wattage equals transformer rating required. Example Of Multiple LED MR16 Transformer Loading
It is worth mentioning at this point that all manufacturers state that their LEDs are designed to be compatible with the majority of common household transformers but they cannot 100% guarantee that they work with them all as there are so many makes and models on the market today.

When connecting 12v LED bulbs that are not compatible with, or overloading a transformer you will see the light flashing on and off or even not lighting at all. At this point it is worth double-checking the transformer rating against the equivalent wattage of the LED before reporting a possible fault or incompatibility issue.