Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [poe]

Power over Ethernet, a set of IEEE standards for transmitting electrical power along with data through an Ethernet cable.

Power over Ethernet, a set of IEEE s for transmitting electrical along with data through an cable.

For other ways of sending both power and data simultaneously through the a single cable, see .

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How safe is 48V DC?

In many Power over Ethernet (POE) setups the transmission voltage is 48V or slightly more. While higher voltage has obvious efficiency advantages, how safe it is? Is there any risk of electrocution when accidentally exposed, in particular to…
Petr
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Bob Smith Termination with POE

I'm looking into doing a Bob Smith termination for a Power over Ethernet (POE) PSE. The TI app note shows the following termination: But all of TI's reference designs (and later figures in the same document) use the following termination with two…
aghoras
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Easiest and Best PoE Ethernet Chip/Micro/Design for DIY Interface with Custom Arduino Board (AVR Solution)

I am looking for a PoE Ethernet chip that I can incorporate in a design I plan on using along with some of the Arduino features. I would prefer to implement a standalone mcu for the Ethernet device capable of providing Ethernet. All possible…
ThaKidd KG5ORD
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What is ORing and why is it named ORing?

I read some documents like the PoE application, it used ORing to protect the reverse input current. I would like to know what ORing is. I googled it, but I cannot find the answer. It seems like a diode or something the datasheet uses diode to…
EEC
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Which type of Ethernet magnetics should I choose for PoE?

I'm trying to find a suitable PoE MagJack for use with my Phy, KSZ8051MNL. The problem is that I can't find one with the same suggested magnetics topology. The closest one I can find has one extra inductor. Suggested magnetics on the left. Available…
Rocketmagnet
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What's the connector on this PSU for a PoE switch?

I bought this switching power supply (PAC-500WA-BE) that I plan to use to power a PoE switch. The documentation is very poor and I would like to know the name of the connector on the back, where the output is. The power supply is supposed to have 2…
leopicchio
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How to design PoE splitter for Mode A and B

I would like to power my device via PoE, but I do not know which mode (A or B) is provided by the 802.3af power sourcing equipment (PSE). How should I design a splitter to accept both implementations: A) the phantom power technique common with…
Edan
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What are the specifics of PoE ethernet magnetics

I have a PoE powered design, and it is currently equipped with magnetics not labelled as PoE, HX1188NL. There is also a transformer with a similar topology, HX2019NL. However, the only difference I can see is the provided isolation. The non PoE…
shodanex
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Doubts related to the Arduino Ethernet with PoE

I implemeted a system by using the Arduino Uno and the Ethernet Shield without PoE. Now, I am thinking to use the Ethernet with PoE but I have following doubts, even if I read the Official Documentation: Is the Ethernet with PoE a Shield? or not?…
Backo
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What to connect to center-taps of Ethernet magnetics?

I'm designing a couple of PCBs to send data and be powered over Ethernet, however, I am not entirely sure what to connect to the center taps. I've heard different suggestions, from connecting it to 3.3 V to isolating them and connecting them to…
Cole Weber
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Does power delivery over ethernet always have to use isolated DC/DC converters?

I am examining the possibilities for building a cheap ethernet device that would be powered over ethernet using PoE technology. I came across this article which shows the generic block diagrams: Looking around, I always find the DC-DC converters…
Łukasz Przeniosło
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Determining how much current I can actually run through my Cat6 24AWG Cables in my confirguration?

I want to use a CAT6 (24AWG) RJ45 cable to carry a total of 2A at 48V. As per the AWG Chart, I see that the Maximum amps for power transmission is 0.577A but the Maximum amps for chassis wiring is 3.5A. I am not going to be using this cable in a…
Neil Dey
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Safe Powering Methods - Working with Children

I'm carrying out a research project this year at uni, which will include creating small electronic sensory devices for children (under 7) with autism. Obviously, safety has to be taken very seriously. Only relatively small amounts of current will be…
kodamapixel
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Ground loop problem with Power over Ethernet

I am trying to build a weather station, powered using Power over Ethernet. Originally I planned to use a Nanode as the microcontroller, but since the Raspberry Pi is so cheap, I decided it was much easier to use that instead. I bought a TP-Link…
njh
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What does Ethernet 100BASE-T signal look like?

Hey guys what does the signal look like on the right of the transformer (T1) on the data lines {TXD_P, RXD_P}? Just trying to understand what it might look like...Is it a square wave? sine wave? Vmax? Vmin? Assuming a typical PoE signal from the PSE…
be-ee
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