2 lights 1 dimmer

[Joely]

Advice please..
I need to run two light fittings each with 7 x 10 watt 12 G4 bulbs on one dimmer switch? They have transformers. What type of dimmer switch do I need?
Heard lots about buzzing dimmers and overloading so want to avoid expensive mistakes.
Thanks

 

[breezer]

check the transformers can be dimmed first (it will be printed on it)

 

[Steve]

If the transformer is round and heavy, dont try dimming it, they are not normally suitable for the task. If you can, remove the transformer and fit a small electronic one, which can be dimmed.

Anyhow, if the tx's are suitable for dimming, you'll need 280 watts of dimming minimum.

 

[Joely]

Thanks for your replies.
I checked one of the transformers and it doesn’t say if it is dimmable or not, but in NEXT directory (where I purchased light fittings) it said must use NEXT halogen dimmer switch so assumed that it is. I looked at the transformer and it is electronic.
Purchased a 400W/VA Intelligent Dimmer Switch (because we didn’t want the NEXT shiny chrome one) and light fitting buzzed!
Husband is cheesed off and we are now thinking about going back to a regular switch.
What are we doing wrong? Why the buzzing?