Is any DC voltage supplied from the network cable?
I thought of connecting a network cable to a product i got and have the network cable powering the the product (The product needs only 2V to be powered up).
My idea was to connect such wire (see picture) from the modem to the product.
How do i know what DC voltage does this cable carry, and which wire carries the DC voltage?
I believe you need a splitter, or build the splitter into your product. The power comes over the same lines as the data, I believe as a DC offset of some sort. Haven't really looked into the details.
There is a ton of information and LOTS of products for it now.
The power only comes if the device specifically states that it supports Power over Ethernet, standard Ethernet cables do not ordinarily contain DC voltages.
All 802.1X devices are required to be transformer isolated so DC voltages can not be passed, POE is 802.3af
For standard ethernet cables Pins 1 and 2 are RX and 3 and 6 are TX, Pairs 4+5 and 7+8 carry +VCC and -VCC respectivly, with max ratings of 30-50 volts or so. Use of a DC-DC converter is obviously required for many applications.
You could design a custom adapter that would bring pins 4/5 and 7/8 to outside connections and use them yourself, as stated 10BT adapters are required to be transformer isolated so it's safe even if the card/connector are wired wrong. For the voltages you're askign for it's not complicated, however currents must be kept low or it will interfere with the data side of things.
That's all covered in the Wikipedia article smanches. The implementation would also be identical except the wires not ordinarily used on 10/100BT ethernet would have to be wired straight through. I would however be incredibly paranoid about power filtering if you intend to get the fully specificied bandwidth of gigabit ethernet with power going over it. Common mode noise reduction is limited in the real world =)
Thank you very much guys.
I read about the POE technology.
I didnt quite understand how the Network Switches work yet, but i'll get to that also.
My product is powered up by 2V-3.6V.
Is it possible to get a voltage at this range from the Category 5 cable?
I read that the min voltage available is 44V, is it possible to somehow get (much) less than that?
They, meaning electronic component manufacturers. Should be able to find them online at any decent electronics place. I know Digikey and Mouser both have them.