FreeLists / si-list / [SI-LIST] Re: What is correctly placement of Transformer? Locate Near IC or RJ45 CONN? Why?

[ªü¥È <binchuan2000@xxxxxxxxxxxx>]

Thanks for your kindly reply, and if this rule of thumb can be used 
in POE(Power Over Ethernet) as well?

Binchuan, Wang



--- In si-list@xxxxxxxxxxxxxxx, "Curt McNamara" <CurtM@...> wrote:
>
> Since Ethernet wiring can be routed through areas with AC, the=3D20
> possibility of accidental connection of AC to Ethernet exists.
> This is why the transformers are rated in KV. Safety standards
> have minimum spacings that must be maintained between dangerous=3D20
> signals (in this case Ethernet) and low voltage signals 
(sometimes=3D20
> identified as SELV). The easiest way to enforce this is to keep=3D20
> the Ethernet transformer near the edge of the PCB and keep 
traces=3D20
> and planes away from line-side Ethernet signals and the 
transformer.
> 
>                                       Curt=3D20
> 
> Curt McNamara. P.E.=3D20
> Senior Electrical Engineer=3D20
> Logic Product Development=3D20
> 411 Washington Ave. N Suite 101=3D20
> Minneapolis, MN 55401=3D20
> Tel 612-436-5178=3D20
> Fax 612-672-0443=3D20
> curtm@...=3D20
> www.logicpd.com=3D20
> This message (including any attachments) contains confidential =3D
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should =3D
> delete this message and are hereby notified that any disclosure, =3D
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> 
> -----Original Message-----
> From: si-list-bounce@... [mailto:si-list-bounce@...] =3D
> On Behalf Of =3DAA=3DFC=3DA5=3DC8
> Sent: Sunday, February 26, 2006 7:52 PM
> To: si-list@...
> Subject: [SI-LIST] What is correctly placement of Transformer? 
Locate =3D
> Near IC or RJ45 CONN? Why?
> 
> 
> Hi all,
> 
> Do you know whta's the correct placement of transformer of 
10/100=3D20
> Ethernet?=3D20
> 
> Should it be placed near Ethernet control IC or near RJ45 CONN? 
For what =3D
> reasons? EMI? Function?=3D20
> 
> Why?
> 
> If you can help to give me some information is appreciated.
> 
> Thanks you in anticipation,
> 
> Binchuan, Wang
> 
> 
> 
> 
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