Connection issues post Storm

Hi all,

I was hoping someone might be able to help me with a little trouble shooting. On coming home today after the Brisbane storms the lights in my house did not work. There is power to all the cbus units, however, some of them do not have the cbus light on. Also the switches in the house to not work, although some of them still have leds on. I disconnected a cable between a 12ch light relay and a 4ch dimmer as the 12ch had a light on and the 4 ch did not. After I disconnected the cbus light came on (I can only assume power and connection has come from the other units connected). If I connect the cable back up it disconnects from the network. Most of the lights now work, however, some do not and I suspect I have broken the connection between some of the units.

Any suggestions on how to find out which bit is broken?

 

Hello,

I have a couple of jobs that this happens to at regularly after larger storms.. Funnily enough at each them its always each sites specific same issue.. Its always dimmer or relay units with powersupplies which have died, but dont show signs of it, ie lights still on, manual control etc, but they bring the cbus network down when connected..

Basically the first time to each site, i went and disconnected all the switchboards from the cbus field network, then connect a pc interface and scan just the relay/dimmers, generally you can tell without scanning though as the cbus light will come up on the ones that are ok, and the failed ones wont..

i have not yet had a site affected by storms which was anything other than a relay or dimmer.. But if you do the above and they all test ok, then its a matter of process of elimination, depending on the size of the install i would go and start removing input devices until normal operation returns, touchscreens first then switches then sensors..

 

Thanks, I will start the process

 

Hi Roosta,

I have isolated the problem to a small external group of items containing a 4ch DIN relay, an ELV and a switch. The 4CH relay has its own power supply.

When I turn off power to this area separately through the circuit breaker, the network communication works fine. The Neo switch still communicates and turns on other lights etc.

I assume this means that the power supply to the 4ch is faulty. Do you think this assumption is correct? Can you specifically test this? Is there a way to turn the power supply off besides removing mains power to the unit?

Thanks
Glen

 

Hi glen,

Thats interesting.. I have one of these jobs where a 4ch powered relay always fails.. Its located in a shed for controlling the tennis court lights, and only has a 4g switch there for control, plus a cbus feed to the house..

I would assume your diagnosis to be correct.. Unfortunately for you it probably means the 4ch relay is only good as a paper weight now.. Not sure if clipsal still offers repairs on these items..

In the house mentioned above, we have surmised that the problem is caused by lightning strikes in the vicinity, and unfortunately the cbus relay is the weakest point.. After the last failure, about a month ago, the customer requested it be removed and reverted to conventional wiring, as the replacement costs were becoming more than he wished to continue paying.. Unfortunately for him i fear that something else is just going to fail under a lightning strike.. A work mate pulled the relay apart and told me it was noticably burnt inside, and he had diagnosed the strike must have come up the load feed, and took out a couple of components on the pcb..

 

Thanks Roosta, seem about right, however, the only weird thing is that the group (which is in a shed) works ok on its own (ie network isolated). I might try disconnecting mains just from the unit and let the network power the relays.