Finding fault in input unit

Hi all,

About once or twice monthly all my input Saturn units flash orange/blue and become unresponsive. It usually behaves again on its own after a few hours.

Ashley here suggested I check all 10 dimmers to see if I have a faulty power supply. I isolated the dimmers and all 4 PS dimmers are out putting 28v or more. Diagnostics also shows all green on input and output units when the network is in a stable working state. The power supplies seem to be working fine. Then I discovered something interesting.

When the orange/blue flashy thing happened again I unplugged and plugged in the RJ45 I have going from my input unit patch panel to a dimmer and all input devices work normally. I effectively isolate ALL input units and reconnect them again.
(Quick explainer..... I'm like Arthurk... I fabricated a 24-port RJ45 patch panel and all my 24 input units patch in there centrally... I know... LAN star topology vs C-Bus daisy chain ideology).

At least I have a solution. If input units go wonky I unplug and re-plug a cable. Voila, but ugly.

I'd like to find out which input unit is wonky or which input cable is wonky. If this phenomenon happens monthly and I use the unplug/re-plug method on individual input units/CAT5 runs it will take 2 years to isolate. :-(

Do any of you have any thoughts on the issue or how to isolate the problem?

Thanks,
Enda

 

mmmm....
You checked the cbus voltage across the plus/minus and what your seeing is ok.
Did you also check the voltage on each cbus wire with reference to ground... they should be a very close match. An unbalaced unit will create problems.
Regards Trevor

 

Hey Trevor, Hmh, I did not do that. Worth checking at the weekend! Thanks

 

Its unlikely to be an input unit problem, but if you want to follow this path of elimination then remove half the inputs at a time, a little like the old guess a number game between 1 and 10 and you are told its higher or lower than your guess.
I think you will find its a loss of C-Bus clock caused by any of the following:-
Failing power supply.
Poor connection causing noise on the network or loss of the clock being transmitted on to the network.
suggestions what to do if possible add another power supply, reprogram which units are enabled to generate a clock maximum 3 enabled per network.
Check your RJ45 connections
look for excessive volt drops between adjacent pieces of equipment.
Run diagnostic utility as long as possible hopefully around the time system fails.
Log when the issue happens and see if there's a pattern. maybe when something else is used or a particular time of day.

 

Hi Wonkey,

Ah, THAT is probably THE issue. I only have 2 clocks enabled and one is the Wiser2, which goes offline from time to time and I need to reboot it.

I'll enable three clocks on the dimmers and see what happens. Fingers crossed.

 

Ok, 3 clocks enabled now.... let's observe that for a few weeks.....