RE: 1-wire CAT5

["Hawes,Timothy Edward \(GEG\)" <haweste@xxxxxxxxxxxxxxx>]

> -----Original Message-----
> From: Sullivan, Glenn
>
> Those of you with one wire networks attached to some of your
> structured cabling...
>
> How do you do it?  i.e., is there some kind of standard for
> what pairs to use for what?

I couldn't find one . . .

> I lean towards using the brown
> pair for a power bus, because I believe that the brown pair
> (in the "B" standard of
> termination) is unused in 10/100 networking, which would
> minimize the risk of one of my NICs getting a shock from
> being plugged into the wrong port...

This is what I did. I can't exactly remember which pin to which
colour/stripe, but "power" is the brown pair and data is the
solid blue.


> And how do you interconnect them?  It seems that a patch
> panel with a bunch of bridged ports would work, but is not
> recommended by Dallas without adding switching to only
> activate one segment at a time...

Don't they? Oh bu**ger, that's exactly what I've done, although I don't
have many sensors off it at the moment. I've commoned up 12 ports, one
is taken by the feed out to the 1-wire USB adaptor and the rest are for
sensors. The USB adaptor lead is a RJ45 from the patch panel into a
chocolate block, then the other side of the choc block into a 6-wire
RJ11 cord and into the adaptor (see:
http://www.tlc-direct.co.uk/Images/Products/size_3/TLCON15.JPG
if
"chocolate block" doesn't translate :-) )

This arrangement will let me add in a power supply when I connect up the
higher-temperature sensors, although the long term plan is to put it all
in a case so it's a bit neater. I also make the short for parasitic
power supply at the choc block instead of at the sensor end -  this
means I can make all the sensors the same and just power the lot when I
add the high-temp ones.

> Glenn Sullivan, MCSE+I  MCDBA
> David Clark Company Inc.

HTH,

Tim.