Problems with Dimmer Module

Hi,
Just wondering if anyone can help. One of my 8 channel dimmers modules (L5508D1A) seems to have stopped working as all of the lights/fans connected to it don't work, and there are no LEDs illuminated on the module (even the LHS c-bus and unit LEDs are not on). My first thought was I need a new L5508D1A, but when I scan the network through C-bus Toolkit software, it finds the module, however, it won't let me manually switch lights/fans on through the software from this dimmer module. Surely if the L5508D1A was dead, then it wouldn't register it on my network.
I also find that I get a lot of input units not responding (and the error 3036) after a network scan (including units connected to my other dimmers and relays, which appear to all be working fine). Before I fork-out for a new L5508D1A which may, or may not be my problem, does anyone know what could be going on with my system, and how I can track the fault prior to buying any new components?
Thanks

 

Are you sure it has power to both sets of 240V terminals?
Circuit breaker?
It will still scan without power.
You whole network may be playing up a bit because you lost a power supply.

Installation instructions and LED indicator description here.
http://www2.clipsal.com/cis/technical/product_groups/cbus/output_units/din_rail_dimmers

Use an electrician.

 

Hi DarylMc,
Yes, both sets of 240V terminals have 240V power.
The system has been installed since 2002 and has worked perfectly except for one dimmer unit that I had to replace a couple of years ago, but when that one failed, it wasn't evident on the network.
I wasn't aware that the scan would pickup the unit if it doesn't have power. Therefore, do you think there is an internal fault preventing the 240 power at the terminals reaching inside the unit? Do you know of any other tests that I can do?
Thanks

 

I always like to hope it might be something simple.
If the LED's are not lighting and it has power at both sets of terminals sounds broken to me.
I tested a working 8 channel dimmer and it scanned with no power applied.

 

If the Dimmer has an in-built power supply it may have died which may also explain why you are having problems with the rest of the network. Measure the Cbus voltage with both the unit powered off and on. If it has a power supply you should see a voltage rise when powered on.

 

Hi Ashley,
How do you power the unit off unless you turn off the main circuit breaker switch which would kill power to the whole thing including an in-built power supply, or are you saying that there could be an in-built battery back-up within the unit which could be dead?
Thanks

 

Dimmers come with and without an inbuilt 200mA power supply. A suffix of P on the model number tells you it DOESN'T have a power supply. Newer units also have it printed on the top. If the power supply fails not only will that unit stop, but because it is also supplying power to the rest of the network there maybe insufficient power available and the network voltage will drop to a level where you will get error in scanning (and operational errors if it drops low enough). To test this, turn the dimmer off at the breaker to disable the power supply and then check the network voltage (across the cbus terminals). Clipsal recommends at least 15 volts but in my experience 20v is about the lower limit. for reliable operation (since other distant devices may have lower voltage). Then turn the power back on and measure the voltage again. If the unit has a power supply the voltage should rise noticeably. If it doesn't you have a dead power supply.

 

Thanks for the advice Ashley,
My unit doesn't have the suffix 'P' so as you say, it must have an inbuilt 200mA power supply. I've therefore carried out the voltage checks and sure enough there is no voltage across the C-Bus terminals on the subject dimmer unit. All my other units give me about 23volts across the terminals. Therefore, I guess I'll need to buy a new dimmer module.
Thanks again