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 > information intended for a specific individual and purpose, and is =3D > protected by law. If you are not the intended recipient, you should =3D > delete this message and are hereby notified that any disclosure, =3D > copying, or distribution of this message, or the taking of any action =3D > based on it, is strictly prohibited. > > > > -----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 > > > > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@... with 'unsubscribe' in the Subject field > > or to administer your membership from a web page, go to: =3D > //www.freelists.org/webpage/si-list > > For help: > si-list-request@... with 'help' in the Subject field > > List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > List technical documents are available at: > http://www.si-list.org > > List archives are viewable at: =3D20 > //www.freelists.org/archives/si-list > or at our remote archives: > http://groups.yahoo.com/group/si-list/messages > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > =3D20 > > ------------------------------------------------------------------ > To unsubscribe from si-list: > si-list-request@... with 'unsubscribe' in the Subject field > > or to administer your membership from a web page, go to: > //www.freelists.org/webpage/si-list > > For help: > si-list-request@... with 'help' in the Subject field > > List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > > List technical documents are available at: > http://www.si-list.org > > List archives are viewable at: > //www.freelists.org/archives/si-list > or at our remote archives: > http://groups.yahoo.com/group/si-list/messages > Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu