Re: [8023-POEP] List of questions regarding cabling and connector s
Martin-
I do not believe that we have the ability to rule this case out.
It is a legitimate configuration under ISO/IEC 11801.
geoff
At 01:10 PM 9/14/2005 , Patoka, Martin wrote:
The
case that might have driven the statement is locals that put two ethernet
channels per 4 pair cable ...
This would be 2, 2 pair implementations. It was unclear to me if we
have chosen to rule this cae out totally.
Martin
Martin Patoka
Systems Engineer
Texas Instruments
214-567-5487
mpatoka@xxxxxx
-----Original Message-----
From: owner-stds-802-3-poep@xxxxxxxx
[mailto:owner-stds-802-3-poep@xxxxxxxx]
On Behalf Of Yair Darshan
Sent: Wednesday, September 14, 2005 3:56 PM
To: STDS-802-3-POEP@xxxxxxxxxxxxxxxxx
Subject: Re: [8023-POEP] List of questions regarding cabling and
connector s
Hi Steve,
The meeting right now is addressing the questions we have to the ISO/IEC
committee.
Regarding the validity of Jo's work I have also noticed this point and as
I mentioned earlier his work requires further review since few
things there obviously not reflecting our system behavior. I'll review it
in details and we will discuss more on it.
Yair
From: owner-stds-802-3-poep@xxxxxxxx
[mailto:owner-stds-802-3-poep@xxxxxxxx]
On Behalf Of Steve Robbins
Sent: Wednesday, September 14, 2005 10:31 PM
To: STDS-802-3-POEP@xxxxxxxxxxxxxxxxx
Subject: Re: [8023-POEP] List of questions regarding cabling and
connector s
Regarding the issue of cable heating, I have a concern about Jo Wallings
analysis. In his supporting document,
"walling_2_0905.pdf" the last sentence in the second paragraph
states "...under the assumption that all pairs in all cables are
energized with the same current."
This is a valid assumption for
PoE Plus, since it appears very likely that we'll use a 4-pair
system. But Jo's assumption is invalid for 802.3af since only half
of the pairs are carrying current.
So I think Jo overestimated the
heat dissipation in the cables (for 802.3af) by a factor of
2.