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802.3af PoE over 2 pairs?

Hello, I have a Cat5e wire in my wall that I need to split to connect two access points.

Can I run two pairs for each access point with PoE?

If yes, what is the pinout I need to use on the RJ45 connectors?


No, even without POE, you’d need a switch.

There exist switches like USW flex (not the mini version) that can be POE powered themselves and can provide POE out on other ports.

(Technically, for 100mbps you only need 2 pairs, but POE gets complicated as well and the whole ghetto setup gets sad quickly, easily).

If you’re looking to use a POE switch normally only power able from a barrel jack, powered through a POE splitter, check the power budgets.

Of course I am going to use a PoE switch, I just need to split one cable to two. Is there a pinout I can use?

Why? What is it you’re trying to achieve here?

You’re misunderstanding, you’d need (another) POE switch.

Gigabit needs all 4 pairs and modern POE needs the device and switch to negotiate.

For 100BASE-TX ethernet you’d use pins ~1,3 & 2,6~ 1,2 & 3,6 on either end of your single cat3/cat5e/cat6/… for 2 devices using the total of four pairs you have in the cable). And you could use a “POE” splitter with a pair of passive injectors depending on what POE standard your switch uses (midspan/endspan).

Standard / cheaper / preferred way to deal with this is to deploy (another) small switch to the point where you need POE Ethernet to be split. (e.g. a Ubiquiti usw flex, or a Ubiquiti nano flex or a Netgear GS105PE; depending on your POE / manageability requirements).

I think you are not getting it.

3 floor house.
Ground floor: DSL modem/router and 802.3af PoE switch.

Single Cat5e cable to first floor.
Single cat5e cable from first to second floor.

I want to add an AP on each floor. Only way landlord will let me is to use the existing cable in the walls.

I know I can use a PoE switch or a PoE passthrough AP on the first floor but I want to cut down on cost, equipment and clutter.

So, I thought I can use two pairs of the ground-to-first floor cable to power the first floor AP at 100Mbit and then join the other two pairs to the first-to-second floor cable and use them to power the other AP.

Both APs would be powered by the ground floor switch by separate ports.

So, my question is simple, is there a 2 pair 802.3af PoE pinout for the RJ45 connector to power an AP at 100Mbit/s?

I am not looking for suggestions on how to manage this, I already know of all the alternatives.

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Here, I found it, under Pinouts / 10/100 mode A,
mixed DC & data

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