Comfort Automation/ Security System Forums

Hi,
The last few days I have had a few instances of coms failure alarms on my comfort system.  I have 2 keypads, 4 scs\'s a ucm etch and a ucm velbus. I have completed no work or upgrades on comfort over the last few months, so nothing has been done to introduce this as far as I can tell.
It started as a keypad failure, and another time as an scs failure, and this evening everything started failing. I also dont seem to be able to log in via ethernet either, although my velbus is working fine via comfort.
Any help in a bit of troubleshooting would be much appreciated.

Regards,Eamon

ok, looking a bit bizzare now. I started to disconnect all my scs switches to see if one was causing he problem, and started to notice a pattern. It seems I get comms failure when a specific velbus relay is activated!!

I have one channel on a vmb4ry for turinin on the central heating, an without fail, whenever I turn it on, the comms failures come on, and clear when i turn it off again...

Doesnt happen with any other velbu channel, just this one.

Have just upgraded comfort firmware to latest. UCM velbus is at 5.2.3 thouh as I hadnt upgraded this due to not being able to do it via comfigurator.

Will look at upgrading it towards end of week, but I cant see how that would be the problem, considering that it had been working fine for years and I have not touched it for months, and the last firmware upgrade I did on comfort was early this year.

Its very odd that the activation of the velbus channel causes the problem (when activated either via comfort, or via velbus pb input)

When you activate a velbus relay, you get communication failure. I think you can check the wiring of that part. It does not look like programming problem, just in case, you may send your cclx file to support@cytech.biz . I will help you check the programming.

Hi Martin,
Thanks for update, I will forward on my logfile shortly. While not ruling out a wiring problem, there are a few things that make me think it is not.
I will refer to the velbus relay which triggers the comms failure as the water heating relay
1) I have a number of vmb4ry modules, each of them has one connection to the comfort ucm, but controls 4 relays. The water heating relay in question is one of 4 relays on this module, all communicating to comfort via the exact same bus, and the same physical wiring, yet it is only this relay which causes the problem.2) Everything is working fine now this morning, even when the water heating relay is activated.

So, the topology, and the wiring of the suspect relay, just doesnt make sense to be due to a wiring problem, as you would expect the same thing to happen on all relays on that module which communicate out the same physical wiring to comfort.

Regards,Eamon

I think it is not so much a wiring error in Comfort , but what the velbus relay is connected to
For example the relay may be disconnecting the comfort bus or it may be switching some load that causes comfort to be switched off. Communications failure is due to loss of connection on the bus or loss of voltage to the module

Test by switching on the relay, then investigate what causes the communications failures.

Hi slychiu,[size=
][/size]Last night when the problem was occurring, I disconnected the wiring on the velbus relay side so the relay was not switching any power, just in case it was leaking something in to the bus. It made no difference.[size=
][/size]I\'m confused even with that at how even a problem on the velbus out affect the comma bus in comfort, as they are effectively isolated are they not ?

There certainly appears to be some interference. It depends on how the wirings between the 2 systems are connected.
when the communications trouble happens, check the voltages on the UCM modules

OKay, been away for a few days so not had a chance to do much on this, but been at home all day and everything has been working perfectly. Since 505pm every time i turn on the velbus relay related o the water heating, I get a comms failure, and then when I turn it off, it clears.

This has been happening consistently over the last few days, in that during the day time, everyhitng is fine, even when using the velbus relay, but in the evening, problems start.

If it happens consistently at a certain time hen it should not be too difficult to fnd the cause
It is not possible for the cause to be anything related to programming or the behaviour of comfort because this cannot cause  loss of communications. It has to be a physical cause, either loss of voltage on the modules or disconnection