Couple of basic questions regarding dimmer switch

Hi guys and gals.

I have a dimmer switch pretty much identical to this:


By aliterai at 2007-08-06

The minimum wattage is 60W. I am installing downlights and want to test that I have wired up the dimmer switch and dowlight wiring correctly by testing it on just one downlight with a 20W bulb before I wire up the others.
Is it OK to use a 60W minimum dimmer on a 20W bulb?

I am also using a 15A choc block. I read that 5A blocks are used for lights. Is 15A OK?

15amp is fine for a chock block - you may find it is too big to fit in the back box descretly, and may not bite the conductors well - it really depends on the actual make of the block!

As for the loading, not having enough load will cause the dimmer to either flash on and off, or cause it to completely shut down - again, it depends on the make.

Are you using dimmable transformers, and a dimmer capable of dimming transformers?

Thanks for the reply mate.

Sorry, I should have been clearer. The choc block is for connecting up my loop-in wiring from my ceiling rose to the downlight.

I am using 6 20W mains downlights on a 400W dimmer switch. The downlights are halogen and not LED or fluorescent.

Would underloading the dimmer damage it in anyway? Its a Varilight Soft Start dimmer.