A dimming feature is really only required when you are lighting a larger space such as a room – it generally does not play a role in spot lighting. When it comes to spot lighting, it is more common to choose a lamp with the desired level of intensity.
While it is possible to dim LED lights, this requires that you use the correct combination of components, and it also depends on the length of the rail. Philips has stated that the 6,5W and 7,5W lamps are dimmable. Philips indicates that these are dimmable in limited applications and with a select number of dimmers. For long secondary (12V) distances, such as a light rail, we therefore do not recommend dimming the lamps. Since Philips regularly changes the specifications for dimming MasterLED lights, we recommend that you check the Philips Lighting website for further information: www.philips.com/masterledlamps.
The 6.5W has a light output of 440lm (which corresponds approximately to the old 35W halogen lamps) and the 7.5W has a light output of 621lm (which corresponds to the old 50W halogen lamps).
To summarise: while the Combi Rail Pro Light is dimmable, we recommend that you choose not to dim spot lights but rather choose bulbs with the appropriate level of intensity. We recommend that you use LED bulbs as this is less expensive because they consume less electricity and have a much longer average service life. In our experience, the MasterLED 6,5W and 7,5W meet the requirements of most applications.