LED Dimmers:
Recommended Dimmer and Transformer Lists by Manufacturer:
Megaman LED Lamp: Compatible Dimmers List (© Megaman): 
Philips LED Mains Voltage Lamps Dimmer List (© Philips):
Philips LED Low Voltage Lamps Dimmer and Transformer List (© Philips):
Osram LED Lamps and Fittings Dimmer Lists (© LEDVance):
Osram LEDvance LED Control Gear (ECG) Compatibility Lists (© LEDVance):
LED DIMMING: Instructions for Using Dimmers with LED Lamps
Without Dimmer: Calculation method for lamp number per transformer – without dimmer
To estimate how many LED lamps can be connected to an existing halogen transformer, the rated power of the transformer needs to be divided by the LED lamp replacement Wattage. For example there is a 150W transformer available, and the MR16 7W (replacing a 35W halogen lamp) is going to be installed. The calculation in this case is as shown.
With Dimmer: Calculation method of lamp number per transformer – with dimmer
Where dimmable low voltage LED lamps have to be connected to a dimmer, the following approach is to be followed:
- Determine the max loading of both your transformer(s) and your dimmer: either in Watts(W) or Volt-Amps (VA).
- Use the ratios below to determine a ‘System Max’ and ‘Branch Max’
- Limit total lamps you can install by ‘System Max’...
- …and ensure transformer load is sufficient to allow for each individual ‘Branch’
More Background Material on LED Dimming (content from Philips website)
A list of frequently asked questions covering all aspects of dimming:
