Universal Dimmer issues

I have almost finished a fairly large residential installation that has gone fairly smooth except for one rogue Universal dimmer. The unit in question has 4x12w LED DL's on channels 1 & 3, 2x12w LED DL's on channel 2 and a LED wall light (with remote driver) on channel 4. The lights come from a high end lighting company who maintain that their lights are c-bus compatible with Universal dimmers.
The issue is that all three banks of dl's flicker to varying degrees with one of the banks of 4 (C3) actually switching off completely after a few seconds. The wall light works ok whilst on but flickers when switched off.
I should mention that there are 4 other dimmers on the job with the same dl's with almost no problem ( i did notice one set of lights flicker a couple of times shortly after powering on but seems to have stopped).
After trying a few things i eventually took down one of the dl's on C3 and plugged in a iron core tranny that i had in the van. Doing this not only fixed ALL problems including flickering/flashing on other channels but enabled the dl's to dim right down to zero.
I would say that i have found a fix but i noticed that on the dimmer unit the indicator for C3 was at first flashing orange/green indicating a short and that the indicator for channel 4-the wall light-was red which according to the help file in toolkit means "other card"-whatever that means but the wall light works perfectly. After powering down all devices and restarting, the flashing orange/green changed to flashing orange but the red light remains.
A system test was all good with no faults reported.
Does anyone have suggestions as to what the problems might be?

 

Hi jonnyp64
For the LED's which won't turn off or flicker in the off state Clipsal Load Correction device 31LCDA should fix that.
Much like the way having an iron core transformer load does.
If you could mention the actual LED fitting in question could probably help other people.

 

Hi Daryl.
Yes, i thought that the 31L would do the job, i just happened to have an old tranny in the van and thought i would try it. Im reluctant to name the fittings because my forum name gives away my identity to easily and you never know who is reading these posts and wish to avoid an argument!!
Do you have any thoughts on the flashing orange light, why the transformer fixed the issues across all channels not just C3 and what "other card' means??
Cheers, John.

 

Hi Jonny64,
To add more light, I have notice on some installations of mine the 31LCDA is not always a lasting fix. I have had to replaced them after 12 months or so in some circumstances. Prior to the 31LCDA becoming available I used iron core tranies (the electrical kind) and have no memorable failures. Tim

 

Umm, thanks for above. I have uplighters in downstairs hall and 2 sets in upstairs landings, all have LEDS but I have had to add a single incandescent lamp to each chain to get correct dimming and for dimmers to be off when they are supposed to be off. Also in lounge, have 2 different chains, one with 11 LEDs and the second with 5 LEDs, former won't dim properly but latter does.

Do I need a Clipsal Load Correction device 31LCDA on each chain of LEDs?

 

Yes that's how its suppose to work. the problem is the Triacs in the C-bus Dimmer unit are not designed to operate with such low current flow and not enough load on the output to stabilize the Triacs chopping of the 240v waveform. Adding one fulfillment globe to any given dimmer output satisfies the Triacs output and make the chopped waveform 95% consistent. I say 95% because if you look closely at LED DLs dimmed to 25% bigness with a filament globe or 31LCDA in circuit to stabilize the dimmer you will notice small fluctuations of the light output. About 5-10% shift up and down around the 25% mark. This i believe is the variation of the incoming 240v to the premise as the 240v is never a consistent 240v.

If i were in charge I would make all lighting in Australia conform to 50Volts DC with color coded cable to differentiate from 240v power cables. So all house have 50v DC for lights and there for new dimmers that wont flicker or have Triac insatiability issues.

Side benefit - less handymen electrocuting themselves when changing a bulb

 

Yep sorry your right. My last post referred to the 8 channel dimmer unit (Leading edge)

 

Cheers Nick.