[NoCatNet] Power over Ethernet problems

[Matt Townsend]

I wonder if you might get a reply by posting this over at the board 
at http://www.linksysinfo.org/index.php

At 04:39 PM 7/17/2007 -0700, Gordon Stewart wrote:
>This is an FYI to the group on problems I've had with POE.
>
>POE is Power Over Ethernet which uses a Linksys WAPPOE device using two of
>the spare wires in the cat 5 cable to carry power to the device at the other
>end - a WET11 in my case.  At the supply end the injector puts 48 VDC on the
>unused pair and the splitter at the other end knocks it down to the required
>5 VDC which powers the WET11.
>
>My setup consists of a WRT54G > POE injector > 50' Cat 5 cable > POE
>Splitter > WET11 > antenna.
>
>I've recently been having frequent interruptions in service where I have not
>been able to ping the WET11.  I can cycle the power, fiddle with the cables
>and eventually it comes back on line.
>
>The cat5 cable is commercial 50' cable with RJ45s on each end.  I noticed
>recently that the RJ45 at the injector end where it plugs into the POE is
>blackened as if it has been overheating. There are carbon deposits on the
>connectors and it is easy to see how the connection may be impaired.  The
>splitter end looks good with no damage.
>
>During a service interruption this morning I dragged a power cord onto the
>roof and installed a 5 volt supply to bypass the POE equipment completely.
>The system came on line immediately.  I have now installed permanent 110VAC
>power to the WET11 at the antenna.
>
>It is possible that I had a bad connection bewteen the RJ45 and the injector
>and this cooked the RJ45.  Perhaps the RJ45 was not designed to carry even
>the low power required to drive a remote device.
>
>Gordon
>
>
>
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