New strange problem with dimmer


since a few weeks I’ve a new phenomenem with one of my dimmers.
When I push the switch (“a” switch because it’s not just with the same switch), the light flashes and goes back out. This repeats itselfs a couple of times (after every push on the switch) and the the light will go on as normally intended to. The load on the dimmer are halogene spots with electronic transformer (dimmable), the dimmer is setted up as dimmer for inductive loads, controled by several switches.
Is this a software error or do I 've to try to set the dimmer to resitive loads?

Second, a few months ago I send one of my dimmers to your technical service to have a filter installed in my dimmer as test to get rid of the influence of the cab signals. This wasn’t efeective, now is my question: the electric store where I sell my switching gear sells small RC filters to put over the load as a filters for cab signals. Could this be effective because I don’t know what kind of components they’ve installed in my dimmer (problably some kind of same setup). I just want to know this before I do this investment because those signals are getting really annoying (half the house is flashing at te time of those signals and thats not really a pretty sight)

Just a tought: as far as I know electronic transformers are capacitive loads, not inductive loads, so the dimmer should be set accordingly.

As for the filters, they should be put in the supply line of the dimmer, not over the load. We do not have any experience with these filters (nor with CAB signals).
Can be worth a try tough.

ok I’ll set the dimmer for normal load and try it out.

As for the cab filters that they sell, they really have to go parallel over the load. I’ll think I’m going to try one out.

They will not be effective when parallelled with the load.
Most likely, the flicker is caused because the dimmer has troubles detecting the zero-cross of the mains, due to the CAB signals that are superimposed.
Therefore, the mains need to be filtered before it enters the dimmer. Doubt that the filter will be effective for CAB signals, which are in the kHz range.

Jeroen, please keep us posted on your progress regarding the CAB signals, I had hoped Velleman would keep us informed about this in the Flickering Dimmers thread but I was painfully mistaken…
The problem with the dimmers is driving me insane.
Do you have a make and model on the filters you mentioned?
The CAB signals in the region of Antwerp are sent at 1347Hz by the way.

Note: We are still working on the subject, however, there is very little info available on the subject, it happens only a couple of minutes per day, so it is hard to test and furthermore, it does not happen in our part of the country.

VEL417, that’s why I asked in the other thread if you guy’s had any ideas, so I, and maybe others who live in problematic regions, could test your ideas for you.
I’m willing to take this a long way if needed as I think it’s an interesting problem and it would be nice to find a solution if we could work together.
But I understand that for Velleman it’s would be a lot easier to make a new revision of the dimmer with better zero crossing detection, the downside for us is that we would still be stuck with unwanted lightshows or would have to buy the new dimmers…


I wonder if its possible to us an lowpass filter like they use in frequency inverters ( eg vf in a lift)?

I will try to use a mainsfilter that are used in eletric equipment. Tension is 250V and max current is 10A. The price is about 5€.

Not sure this will work. Bandwidth is most likely too high, CAB-signals will probably pass.
Anyway, it is worth a try. All info is welcome.