Re: 1 wire temperature monitoring

[Kevin Hawkins <yahoogroupskh@xxxxxxxxxxxxxx>]

Hi Nigel,

Interesting - do the three legs support both parasatic and powered /
three wire operation ?  I had a lot of troubles with parasitic powered
devices but when I moved to three wire 'powered' setup all the sensors
appear to function fine - around 70 m of cable length (CAT5) and 30
sensors - mostly 18B20's. I know from other posts that getting it
working reliably is a bit of an art though.

I'm currently using OPNone (link below) which is again Ethernet
connected and uses xAP so directly integrates into any xAP aware app
including HomeSeer. It has some additional 'smarts' including monitoring
sensor values and issuing xAP commands directly to other devices
automatically based on logic/threholds and the time.  eg it can turn on
your boiler if the temp goes below certain levels.  It doesn't have the
three independent 1-wire legs though and it has around a dozen specific
1-wire devices it supports rather than yours which say 'all' - so I
think you'll be better with the one you found.

http://www.opnode.org/dokuwiki/doku.php?id=projects

Kevin

Nigel Giddings wrote:
> Hi,
>
>
>
> I have been looking at extending my 1-wire temperature monitoring in
the house. 1-wire was never designed for long cable lengths and begins to
suffer reflections if the cables get too long... well I have reached that
point.
>
>
>
> I want to monitor some of the H/W pipes to things like the showers and
baths, to trigger towel rail heating and also temperatures on the heat
exchanger to see if it actually exchanges heat as well as a couple more
room and equipment rack probes....
>
>
>
> However, I have run up against the cable length issue.
>
>
>
> What I have found is a Hub that effectively separates three daisy
chains of sensors to enable three lengths of cable with sensors.
>
>
>
> http://www.homechip.com/catalog/product_info.php?cPath=22&products_id=109
>
>
>
> What is also nice about this is that it connects to the PC via
Ethernet so you can remotely position it wherever you have Ethernet
connectivity, even over the internet....
>
>
>
> I intend to use with Homeseer with a plug-in called Ultra1wire to do
all the leg work and place the data into virtual devices in Homeseer which
can then be used however I want.
>
>
>
> http://forums.homeseer.com/forumdisplay.php?f=854
($29.95)
>
>
>
> They are in stock, spoke with them today, and will probably order 1 on
Monday (£99 + VAT + P&P £7)
>
>
>
> Just thought I would pass it by the list to see if any other
alternatives exist....
>
>
>
> Nigel
>
>
>
> [Non-text portions of this message have been removed]
>
>
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