Gigabit PoE - component solutions?

[Clifford Heath]

I need a inexpensive (i.e. not packaged) solution to delivering clean
Power over Ethernet at gigabit rates. Yes, I know that balun imbalance
will limit how clean it can be - but I'd still rather not bring
unnecessary noise into the remote (box (a radio).

I don't want to buy a commercial packaged solution for injecting power,
because most don't care at all about noise (I've measured *volts* at
hundreds of KHz), and they're expensive.

So I'd like to find a passive gigabit Ethernet isolator - a pair of RJ45
sockets with magnetics, so I can inject my own power from a cleaner
supply. I've come up with nothing in my searches. Can anyone help?

At the powered end, a normal Gbit Ethernet socket (with magnetics) is
acceptable - but they're still over $10 or so at stockists. Clearly
those who manufacture routers don't pay those silly prices, so there
must be a cheaper source. Any thoughts?

I could use external magnetics following a simple socket, but I would
still have to route the Gbit traces, so an integrated socket is preferred.

Finally, 4PPoE is allowed to deliver 57V, with the expectation that
after 100m drop across the 4 pairs, it will be 48V. Those voltages are
inconveniently high for most switch-mode voltage droppers. What you use
to drop this to, say, 12V at 3 or 4A?

Clifford Heath.

 

[whit3rd]

On Monday, April 20, 2020 at 5:41:42 PM UTC-7, Clifford Heath wrote:

I need a inexpensive (i.e. not packaged) solution to delivering clean
Power over Ethernet at gigabit rates.

Finally, 4PPoE is allowed to deliver 57V, with the expectation that
after 100m drop across the 4 pairs, it will be 48V. Those voltages are
inconveniently high for most switch-mode voltage droppers. What you use
to drop this to, say, 12V at 3 or 4A?

There's lots of DC converters in the telecom world to fit those specs;
Ericsson's line was sold to Flex, and this one looks like a fit

<https://flexpowermodules.com/documents/fpm-techspec-pku5500e>

 

[Clifford Heath]

On 21/4/20 12:00 pm, whit3rd wrote:

On Monday, April 20, 2020 at 5:41:42 PM UTC-7, Clifford Heath wrote:
I need a inexpensive (i.e. not packaged) solution to delivering clean
Power over Ethernet at gigabit rates.

Finally, 4PPoE is allowed to deliver 57V, with the expectation that
after 100m drop across the 4 pairs, it will be 48V. Those voltages are
inconveniently high for most switch-mode voltage droppers. What you use
to drop this to, say, 12V at 3 or 4A?

There's lots of DC converters in the telecom world to fit those specs;
Ericsson's line was sold to Flex, and this one looks like a fit

https://flexpowermodules.com/documents/fpm-techspec-pku5500e

Yes, the power is the easy bit - though your suggestion is not in the
right budget.

Can anyone tell me about a paired Ethernet RJ45 socket with suitable
magnetics?