CBUS problem, can I bounce an idea off you...

[Paul Gordon <paul_gordon@xxxxxxxxxxx>]

Chaps, hoping some CBUS users out there might be able to help me keep
(what's left of) my sanity. - and restore my faith in the absolute
rock-solid reliability of CBUS kit!



Over the last couple of weeks, I've noticed increasing unreliability with
my
CBUS install.. At first it was quite rare, the very first problem happened
about a month ago, but as time has passed it has become more and more
frequent, and it's been driving me nuts.



In a nutshell, almost every one of my output units intermittently fails
completely. meaning I cannot switch any lights or appliances on that module
on or off.



Most of my output units include a power supply, so my initial thought of a
network power issue seemed unlikely. When the problem occurs, neither the
CBUS or UNIT led's are on, and the local channel override buttons on the
unit do not function - for all intents and purposes the unit appears
completely dead. But the thing is if I scan the network with CBUS Toolkit,
the unit appears, and reports its CBUS voltage (30.2V in this case.) - and
yet NOTHING is working. - I'm looking at one right now. physically it is
dead, but it is talking to toolkit.



On all occasions when this occurs, it seems to just "magically"
fix itself
after some period of time, which can be anything from minutes to hours.



I have just started to formulate a theory, based on a few observations.



CBUS Toolkit is not showing the Line/Mains Present indicator for the units
that are currently "dead".

I just measured the mains voltage supply at the input to the module.. - its
currently reading a mere 196VAC on my multimeter.

The local power supplier has had the mains off in the area for several
hours
today, - following a letter I received about a week ago informing me it
would be off today for essential repair work following problems in the
area.



Now it all starts to make sense.

All this time I've been tearing my hair out because of the intermittent and
sporadic nature of the behaviour. - that pretty much seemed to logically
rule out most types of hardware and/or cabling failure. - although that
hasn't stopped me crawling around the attic/cellar etc. trying to find a
break in the CBUS network cable (I thought maybe a mouse was chewing
through
it somewhere) - but the fact the none of the input units *ever* had a
problem confused me even more with the theory of a CBUS network problem.



I think the fact that my problems only started about a month ago, and the
letter from the leccy co can't be coincidental. - I'm thinking there must
have started to be a low voltage condition on and off. - based on local
demand perhaps? - the problems always seemed to be worse in the evening.



Also adding to the confusion, is that if I'm right, and this *IS* caused by
my mains supply being undervoltage,  - absolutely nothing else electrical
in
the house has exhibited any kind of problem at all. - it's exclusively, and
only CBUS output units that don't like it.



Looking at the manual for the units, it does specify supply voltage
220-240V
- Mine is currently well under.



So my question is this. - on the CBUS units *with* power supply, I'm
guessing it must be true that the CBUS circuitry in that unit can still
function on CBUS network power coming from other powered units.. - even if
the unit isn't on the mains itself. - my observations suggest this is true.
- which is why it still talks to toolkit, as some other units in different
parts of the house are still "alive" and supplying CBUS network
power.

Does anyone know if the CBUS output units really *are* that sensitive to
variations in mains supply? - and if so, might it be true that units
without
a CBUS power supply are LESS sensitive? - because it seems to be the case
that I've never had a problem with a couple of units that lack a PSU.
(although they are closer to the incoming mains well, so that may be the
reason).



Off to complain to the local leccy company methinks!



If you got this far.. Thanks for listening!



Paul G.







[Non-text portions of this message have been removed]



------------------------------------

<*> Join the Automated Home Forums
http://www.automatedhome.co.uk/vbulletin/