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Ethernet transformwer with 4kV isolation

Started by Joe G (Home) March 28, 2011
is there such a beast?

My ethernet circuit floats at ~ 240AC mains and I'd like to use the Ethernet 
transformer for Isolation.

Most I have seen is 1kV

Or should I look else where to put my Isolation barrier.

Regs
Joe 


On Mar 28, 1:00=A0am, "Joe G \(Home\)" <jo...@optusnet.com.au> wrote:
> is there such a beast? > > My ethernet circuit floats at ~ 240AC mains and I'd like to use the Ether=
net
> transformer for Isolation. > > Most I have seen is 1kV > > Or should I look else where to put my Isolation barrier.
This just screams "fiber."
<robertwessel2@yahoo.com> wrote in message 
news:de55cea7-2a28-4279-a54b-b34f0e0c8b4c@d16g2000yqd.googlegroups.com...
On Mar 28, 1:00 am, "Joe G \(Home\)" <jo...@optusnet.com.au> wrote:
> is there such a beast? > > My ethernet circuit floats at ~ 240AC mains and I'd like to use the > Ethernet > transformer for Isolation. > > Most I have seen is 1kV > > Or should I look else where to put my Isolation barrier.
This just screams "fiber." ==> Joe ==> Can you suggest low cost fiber solution? What key word should I be search in Google for? Regards joe
On Mar 28, 2:31=A0am, "Joe G \(Home\)" <jo...@optusnet.com.au> wrote:
> <robertwess...@yahoo.com> wrote in message > > news:de55cea7-2a28-4279-a54b-b34f0e0c8b4c@d16g2000yqd.googlegroups.com... > On Mar 28, 1:00 am, "Joe G \(Home\)" <jo...@optusnet.com.au> wrote: > > > is there such a beast? > > > My ethernet circuit floats at ~ 240AC mains and I'd like to use the > > Ethernet > > transformer for Isolation. > > > Most I have seen is 1kV > > > Or should I look else where to put my Isolation barrier. > > This just screams "fiber." > > =3D=3D> Joe =3D=3D> =A0Can you suggest low cost fiber solution? > > What key word should I be search in Google for?
"ethernet optical transciever" If you can live with fast Ethernet, something like an Avago AFBR-5803AQZ is about $30 in small quantities. Or Gb Ethernet with something like an AFBR-53D5Z is about $50. I think you can probably find fast Ethernet parts down to about $20 (but don't put too much stock in that - in either direction). If you have just one or two problematic installations, an external copper-to-fiber converter ($100-$200 each for GigE) or two is a simple way to deal with the problem.
Joe G (Home) wrote:
> is there such a beast? > > My ethernet circuit floats at ~ 240AC mains and I'd like to use the Ethernet > transformer for Isolation.
Are you saying that you have one ethernet phy at earth potential, a second at ~240VAC and the cable floats? Can you use a gas tube surge suppressor on the cable pairs to earth ground?
> Most I have seen is 1kV > > Or should I look else where to put my Isolation barrier. > > Regs > Joe > >
>> My ethernet circuit floats at ~ 240AC mains and I'd like to use the >> Ethernet transformer for Isolation.
> Are you saying that you have one ethernet phy at earth potential, a > second at ~240VAC and the cable floats? Can you use a gas tube surge > suppressor on the cable pairs to earth
Surely you've heard of Ethernet over Power? -- mac the na&iuml;f
On 2011-03-28, mac <alex.colvin@valley.net> wrote:
>>> My ethernet circuit floats at ~ 240AC mains and I'd like to use the >>> Ethernet transformer for Isolation. > >> Are you saying that you have one ethernet phy at earth potential, a >> second at ~240VAC and the cable floats? Can you use a gas tube surge >> suppressor on the cable pairs to earth > > Surely you've heard of Ethernet over Power?
No, but I've heard of Power over Ethernet. That's only 48VDC though...
mac <alex.colvin@valley.net> wrote:
>>> My ethernet circuit floats at ~ 240AC mains and I'd like to use the >>> Ethernet transformer for Isolation. > >> Are you saying that you have one ethernet phy at earth potential, a >> second at ~240VAC and the cable floats? Can you use a gas tube surge >> suppressor on the cable pairs to earth > > Surely you've heard of Ethernet over Power?
Forgot the ;) -- mac the na&iuml;f
Joe G (Home) wrote:
> is there such a beast? > > My ethernet circuit floats at ~ 240AC mains and I'd like to use the Ethernet > transformer for Isolation. > > Most I have seen is 1kV > > Or should I look else where to put my Isolation barrier. >
You can get medical grade isolation transformers for Ethernet. Not sure how much this one costs but they are usually well north of $100: http://www.baaske-medical.de/product_info.php/info/p478_Netzwerk-Isolator-MED-MI-1005.html/XTCsid/uclhpdj0bctjeufg6sf7pkjkn4 You'd have to ask them where they can be bought in Australia. Or maybe you guys have local suppliers for such transformers. The IT department of a large hospital might know. But I am not sure your 240VAC floating setup is legit in the first place. -- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
Joerg wrote:

> You can get medical grade isolation transformers for Ethernet. Not sure > how much this one costs but they are usually well north of $100: > > http://www.baaske-medical.de/product_info.php/info/p478_Netzwerk-Isolator-MED-MI-1005.html/XTCsid/uclhpdj0bctjeufg6sf7pkjkn4 > > You'd have to ask them where they can be bought in Australia. Or maybe > you guys have local suppliers for such transformers. The IT department > of a large hospital might know. > > But I am not sure your 240VAC floating setup is legit in the first place.
IMHO, I don't think it would pass UL, CE or CSA without approved high side components and creepage distances. Then there's the issue of the cable and connector insulation and touch distances...

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