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This Wiki dosn't describe the way Ubiquity deploys PoE This wiki WILL!


AirMax class equipment is equipped with mode B power over the T568B wiring standard for 8wire / 4pair Cat 5e utp cable.

CAT6 twisted pair.jpg

All AirMax and GL.iNet class devices have 100Mbps Ethernet ports. They receive 24V DC power via the Ethernet port. The DC voltage is injected on "spare pairs" unused by 100Mbps Ethernet. A fixed DC voltage is injected 2-Pair style on (+4, 5; -7, 8).

Poe b mode passive.png


This is a black 100-240v AC to 24v DC 1 amp 100Mbps injector. Its not possible to obtain 1000Mbps port speed with a GB-B240-100, pins 4- 5 and pins 7-8 have been observe to not be connected on the LAN side of the injector.

GB-B240-100side CASE.jpg GB-B240-100side A.jpg GB-B240-100side B.jpg


This is a black 100-240v AC to 24v DC .5 amp 100Mbps injector. Note the reset switch. Pins 4- 5 and pins 7-8 have been observe to not be connected on the LAN side of the injector.

Gb 050 case.jpgGb-a240-050 top.jpgGb-a240-050 bot.jpg

Mikrotik's stock injector

This is a pig tail style Injector for mode B. You need your own source of power. Pins 4- 5 and pins 7-8 have been observe to not be present in the LAN of the injector. This Injector is only for 100Mbps.

Mtik injector.jpgMtik missing pins.jpg


Don't forget the white model, its a white .5 amp 1000Mbps injector.

White u 1000.jpgWhite u 1000 front.jpg


You might ask... How do devices that need to run at 1000Mbps Ethernet ports speeds, receive PoE? The G24102HKG chip is how! Data sheet 26528.pdf.


This is a gray 100-240v AC to 24v DC 1 amp 1000Mbps injector. Power is sent over all 4 pairs with data. The injector are found in the box of AirFiberX and AC-Gen2 devices. Its a Passive 1000Mbps PoE injector as well.

GB-H240-100-4 case.jpgGB-H240-100-4 pcb top.jpgGB-H240-100-4 side B.jpg

Tycon Power Systems POE-INJ-1000-WT Gigabit PoE Injector/Splitter 4 Pair

This is a Gigabit PoE Injector. This injector breaks in or out of the cable. All 4 pairs are isolating allowing for 1000Mbps Ethernet speeds. Unlike the Ubiquity injectors you must supply a power source.


Caution! Connecting passive devices to active 48v DC PoE will damage the device!

Great article that parallel my interest with POE.

PoE Switches

EdgePoint class

EdgePointswitches support 100Mbs and 1000Mbs Ethernet. They supply mode B and 4pair PoE. A few of the devices have the capability to selectively supply "PASSIVE" 54V and 24V PoE.

  • EP-R6 Accepts 4 pair passive 24V DC for as an input source via PoE. The R6 only outputs 2 pair passive PoE.
  • EP-R8 2 ports with selectable 54V or 24V DC 4-Pair (+1, 2, 4, 5; -3, 6, 7, 8) Passive PoE and 5 ports with 24V DC 2-Pair (+4, 5; -7, 8) Passive PoE.

EdgeSwitch class

  • ES-5XP will supply up-to 11.5W of 24V DC 4-Pair (+1, 2, 4, 5; -3, 6, 7, 8) power for each POE enabled port.
  • ES-10XP supports both 100Mbs and 1000Mbs port speeds but unlike the 5XP... The ES-10XP only supplys passive PoE up-to 14W 24V DC at each port 2-Pair (+4, 5; -7, 8).
  • ES-8-150W supports both PoE/PoE+ and 24V DC Passive PoE.

Nanoswitch N-SW

The N-SW is marketed as a 2 pair passive PoE powered, unmanned 4 port 10/100/1000 Mbps Ethernet RJ45 switch. The device is intend to "breakout" devices from a single cat5e cable thats been run up a short tower. We commonly used them to run 2 or 3 devices off of a single cat5e run to the top of a tower or onto your roof. Thanks to W2GMD for discovering that the N-SW contradicts its data sheet... accepting 4 pair or 2 pair passive PoE for input. You must of coarse input 4 pair power be capable of outputting 4 pair Poe for a device. This is where we start to run in to the problems...


The following diagram describes how to properly power a N-SW, with a hAP. The hAP wasn't designed to deliver more than 500mA of current at the port. The fuse limits are independent from the input voltage 9-24v on a hAP! As result of not using an external injector to supply power to the N-SW with 2 breakout devices, the devices down stream of the hAP's port 5 will brown-out causing the devices to reboot!

HAP ac Power.png

NOTE! How Ubiquity devices react when supplied insufficient input power!

Device get can get stuck in reboot loops, if every thing is just right! As the load increases --> The supply voltage falls --> current limits trips --> Device reboots. It turns out that Airfiber is very sensitive! AirMax equipment too!

Examples! How to use a N-SW

The nanoswitch accept 4pair passive poe and 2pair passive poe for power. Then we have 3 types of devices being powered... one type runs 2 pair passive 24v poe and runs at 1Gb port speed. Two a device that runs on 4 pair passive 24v poe runs at 1Gb, and the most common 2 pair passive 24v poe running at 100Mbs.  1Gb devices have power isolation on all 4pairs but may only pull from 2 pairs! Ive found that for an AirFiber3x device to reach full tx power levels while sharing a Nanoswitch with another 2 pair device the Nanoswitch needs to be feed 4pair passive 24v power.

With that said

Af config MDARC.pngN-sw on one poe port.pngN-SW with injector .pngN-SW AF .png