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Hi all, My proposal would be:
4. Regarding
4P vs 2P: Since 2P
is a subset of 4P then I would recommend that: Type 2
is 4P (for PD or PSE) Type 3
is 2P (for PD. If committee will decide to support 2P PSE then it is true for
PSE as well)
5. 4P Current sharing: Should be simply noted as CS = Current Sharing
(also well understood for PS designers)
It can be active or passive and it is implementation issue.
Yair From:
owner-stds-802-3-poep@xxxxxxxx [mailto:owner-stds-802-3-poep@xxxxxxxx] On Behalf Of C S The committee has expressed an interest in standard
nomenclature to be used in presentations associated with high power PoE. Here I
will present some suggested terms to be used in 802.3at. Please respond with
your opinion and feedback on the best terms to use. SUGGESTIONS: SYSTEM 802.3at
PoE: 802.3af PoE: Type 2
PoE Type 1
PoE ***Note 1 802.3at
802.3af ***Note 2 AT
PoE
AF PoE .at
PoE
.af PoE PoE+
PoE PoE
Plus
PoE PoEp
PoE HP
PoE
PoE PSE 802.3at
PoE: 802.3af PoE: Type 2
PSE Type 1
PSE 802.3at
PSE 802.3af PSE .at PSE
.af PSE AT
PSE
AF PSE PoE+ PSE
PSE PoE Plus PSE PSE PoEp
PSE
PSE HP
PSE
PSE PD 802.3at
PoE: 802.3af PoE: Type 2
PD
Type 1 PD 802.3at
PD
802.3af PD .at
PD
.af PD AT
PD
AF PD PoE+
PD
PD PoE Plus
PD PD PoEp
PD
PD HP
PD
PD Notes: 1. Type 1, Type 2, Type 3, etc. This terminology was well received during the meeting
in November. It should be noted that depending on the outcome of committee w!
ork, there might be more than 2 types of PSEs, and PDs. I am referring to PSEs
that can drive all 4 pair vs PSEs that drive 2 pair. If high-power PoE includes
2-pair and 4-pair PSEs, then type 1, type 2, and type 3 would be well
suited. Realize there might be some early confusion because in the near term a
4-pair high power PSE might be referred to as a type 2 PSE. If 2-pair and
4-pair PSEs exist, a 4-pair PSE would probably be better termed as a type 3
PSE. Until the 2-pair/4-pair question is answered, it would be best to clarify
what type of system is being referenced. This nomenclature will also work well to help users
understand which PDs will work with which PSEs. I.E. Type 1 PDs work with Type
1 and 2 PSEs. Type 2 PDs only work with Type 2 PSEs. It makes sense. If there
were 3 types of PSEs and PDs, this same inter-operability tier system would
work. 2. 802.3af and 802.3at Vario! us 802 enhancements including 802.3af have used
the letter designation successfully in the marketplace and to some extent this
helps advertise IEEE committee work. However, it should be noted that the
features defined in the 802.3at committee eventually get folded into the 802
specification and all references to 802.3af and 802.3at are lost. It should
also be remembered that the 802.3at work will result in a clause that combines
both 802.3af and high power PoE systems into one section. -------------------------------------------------------------------------------------- CURRENT BALANCING There are two types of current balancing that will be
discussed in future committee meeting and it will help us if we use a
consistent terminology to describe these two different types of balancing. 4-Pair System, Balancing current in
each of the 4-pair In a! 4-pair system, current is delivered to the load
via 2 pairs (4 conductors) on the top rail. Balancing the current in
each pair on the top (or bottom) could be called: Active Load Sharing (ALS) Active Current Balance (ACB) Pair-to-Pair Balancing (P2PB) Balancing Current in the Magnetics In either a 2-pair or 4-pair system, there may be a
desire to balance the current in each of the conductors of a single pair. This
balancing reduces the offset current in the magnetics and could be called: Magnetics balancing MB) Inter-pair balancing (IPB) Yahoo!
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