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Re: [8023-POEP] Fwd: A timely article




Hi Dan:  I also took Geoff's comments that way as well.  and my thought was
that rather then creating standards which allow larger and larger amounts
of power to be transmitted to the point at which you could have an
"Etherlamp"  (A floor lamp that sits next to your easy chair and
plugs into an RJ45 that you turn on and off via commands from your
laptop GUI.....  LED-based of course to save power...)

Can't we make do with the power levels available today.

EG:  Living within our means??

Best Regards

Maurice Reintjes
MindspeedTM
Hillsboro, Oregon,USA
Office Phone (503)-914-5370
Mobile (503)-701-0797



"Dove, Dan" <dan.dove@xxxxxx>
Sent by: owner-stds-802-3-poep@xxxxxxxx

11/09/2006 09:44 AM
Please respond to
"Dove, Dan" <dan.dove@xxxxxx>

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Subject
Re: [8023-POEP] Fwd: A timely article





Did I see a soapbox standing idle?

I actually read (misread?) Geoff's reference to timliness a bit
different.

Here we are in a world that is growing more and more sensitive to energy
waste, and rather than working on a way to improve efficiency, we are
simply putting out more power at a lower efficiency.

Sending 50V through wires that were intended for low-power
communications rather than high-power distribution is lossy.

The current paradigm, taking AC power at 120/240VAC and converting it to
50VDC with an efficiency hit, then running it through a distibution
network inside a switch (lossy again) then switching it through a FET
(lossy again) then running it through UTP (lossy again) then a DC/DC
converter (lossy again) seems to be going backwards.

I think that PoE is a great technology for low-power devices that are
hard to wire up, but makes little sense for devices that are easily
attached to a wall outlet (laptop?). Rather than driving toward higher
and higher PoE power, we should be driving toward lower and lower
powered PDs... But that is not a standards issue, that is a product
design issue.

All that said, I am not trying to be negative here... But I do have my
reservations about just how much power we should be stuffing down these
data lines.

Dan


------------ Previous Message Below ------------

-----Original Message-----
From: owner-stds-802-3-poep@xxxxxxxx
[mailto:owner-stds-802-3-poep@xxxxxxxx] On Behalf Of Charles Palmer
Sent: Thursday, November 09, 2006 8:01 AM
To: STDS-802-3-POEP@xxxxxxxxxxxxxxxxx
Subject: Re: [8023-POEP] Fwd: A timely article

Team - just my thoughts:

Anything you can do to minimise the standby state power consumption
(both ends) could represent many MWhr or GWhr over the years...

And as for the power loss in those PD bridge rectifiers...

This is big news in the UK at present:
http://news.bbc.co.uk/2/hi/business/6096084.stm

And: European legislation is on the way:
http://ec.europa.eu/enterprise/eco_design/index_en.htm

Regards - Charles Palmer

Geoff Thompson wrote:
> ...for our group too.
>
>
>> Subject: A timely article
>> To: <eee@xxxxxxxxxxxxxxx>
>>
>> http://www.businessweek.com/globalbiz/content/nov2006/gb20061107_4475
>> 69.htm
>> ?chan=tc&campaign_id=rss_tech
>
>