From: Jim S. <js...@sy...> - 2008-01-17 15:02:44
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Brad, I'm using the passive (unpowered - parasitic power during the reading = only)I have in one instance 4 sensors 6 inches a part (pool depth sensor) they = all register the same temperature within about 0.19 degree C when they are = all in the same medium (like all in the water). Your temperature difference sounds like local heating - what current is = it taking? Jim -----Original Message----- From: mis...@li... [mailto:mis...@li...] On Behalf Of = Brad Yarotsky Sent: January 16, 2008 11:36 PM To: The main list for the MisterHouse home automation program Subject: Re: [mh] One wire boards Hey Jim are you powering these sensors? I have played a bit with the ic right on the bus and a power temp sensor like the one from hobby-boards. = And when the units are side by side the temperatures are a few degrees different. Any thoughts on this? Brad > I use the ds9097 with almost 200 ft of Cat 5 cable and 10 temperature=20 > sensors. It works well as a long linear line - it been running for=20 > about 3 years. BUT - don't try to run a lengthy (e.g. more than about=20 > 6 foot) spur line off the linear line - reliability drops quickly due=20 > to the echos caused by the spur. In that case there are lan switches=20 > that turn on and off the segments of the lan - I have the parts but=20 > have not built a board. Bottom line - distance is not the issue, it's=20 > the echos from spur or star wired configurations that make it=20 > unreliable. > > Jim > > ---------------------------------------------------------------------- > --- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > ________________________________________________________ > To unsubscribe from this list, go to: > http://sourceforge.net/mail/?group_id=3D1365 > > -------------------------------------------------------------------------= This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ ________________________________________________________ To unsubscribe from this list, go to: http://sourceforge.net/mail/?group_id=3D1365 |