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Re: [802.3af] Late comment


What I beleive we are missing is that if you tie all of the "GROUNDS" 
together in a PSE
If you put a voltmeter between "hot" leads from 2 different PSEs,
then is the max voltage between the leads (fault conditions included):
         VportMax - VportMin
         2 X VportMax

I contend that any answer above except [2 X VportMax] is OK
We currently have no text to preclude  [2 X VportMax].

It was agreed in Vancouver that this is a problem.

I would happy if you could point to text that would prove me wrong.


At 09:37 AM 1/13/2003 -0800, Roger Karam wrote:
>Hi Jeff
>if you feel this is a must for some reason, please clarify to the group
>we defined that 3,6 is the higher potential! we are floating,
>is this not enough?
>so automatically gnd would be on 3,6... for a -48v supply
>what am i missing?
>At 08:47 PM 1/12/2003, you wrote:
>>During the meeting in Vancouver I asked the group's indulgence with 
>>respect to acceptance of yet another comment from me.
>>There seemed to be general agreement that the comment addressed an issue 
>>that was important enough that it should be accepted.
>>The comment:
>>I can find no place where there is a specification as to which side of 
>>PSI is tied to ground (i.e. negative ground vs. the positive ground 
>>usually found in mid-fifties British sports cars with Lucas electrics.) I 
>>request that a specification be added that dictates which side of the 
>>supply is grounded.
>>This documents my request to add this comment to the database and address 
>>it during the Santa Clara/January meeting.
>>| Geoffrey O. Thompson                    |
>>| Vice Chair,  IEEE 802                   |
>>| Nortel Networks, Inc.  M/S: P79/06/B04  |
>>| 4655 Great America Parkway              |
>>| P. O. Box 58185                         |
>>| Santa Clara, CA 95052-8185  USA         |
>>| Phone: +1 408 495 1339                  |
>>| Fax:   +1 408 495 5615                  |
>>| E-Mail: thompson@xxxxxxxx               |
>>| Please see the IEEE 802 web page at     |