Lighting system has annoying buzz when off

Hi there, I am hoping someone will be able to give me some direction with a problem we?re experiencing with our lighting system.

We rent an apartment that has a CBUS lighting control system which is made up of a CBUS2 L5508RVF 8 Channel Relay with 200mA C-Bus Power Supply and two Leading Edge Dimmers, 1x8 and 1x4 Channel. The downlights are powered by Actec Mini60 Electronic Transformers - 12v Low Voltage.

The problem we?re experiencing is in the master bedroom. When the lights are off, we get a high pitch buzzing sound that tends to oscillate in pitch. I?m able to stop the noise when I disable the power to the 8 Channel Dimmer.

Could the issue be related to the downlights themselves or is it likely to be a transformer?

Are these transformers ok to use with the CBUS system?

Finally, if I was to replace the original downlight globes with dimmable LEDs, which would you recommend?

 

Hi tonyp
The leading edge dimmer makes a buzzing noise at the dimmer unit when the lights are dimmed and this is normal.
Maybe that is not the problem.
The CBus dimmers have a voltage at the outputs even when turned off.
Assuming the noise is happening when the channel is fully off it sounds like it is coming from one of your transformers.
That is not normal and should be investigated.

The ballast you mentioned is in CBus dimming compatibility chart and max 3 per channel on your dimmer as far as I can tell.
http://www.google.com.au/url?sa=t&r...siB7pKAzGoebvALJw&sig2=1PF49dRkBxd408wzA-_fGA

Pierlite has LED downlights and specs for your dimmer.
I have very high regard for this product and would consider looking at this if you want to go to LED.
http://www.pierlite.com/au/87173/starburst-crystal-eco#.Vg-SJ0mhdaQ

It is not the only LED which will work on your dimmer but it is one I think you can trust to work well if installed to the specs provided.
The light source is deeply recessed and it is a very nice low glare fitting.
If you want high light output you should look at other options.