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Powering 3 or more radios on EP-R6 using POE

by ‎08-07-2017 02:56 PM - edited ‎08-16-2017 03:29 PM

The challenge: an existing installation where an EP-R6 is powered by POE and is subsequently powering 3 AirMax radios also by POE.

 

Total power provided to the EP-R6: about 30 watts (30 watts at POE less whatever is lost in the 100 foot cable run).

Total power being used by the EP-R6 and all its underlings: about 30 watts.

 

This situation was causing the EP-R6 to randomly reboot - presumably due to sometimes needing more power than it had available to it and/or temperature changes affecting loss in the cables.

 

The solution: an AirFiber POE with the same amperage output but double the voltage. That means double the watts available at the other end of the cable - 60+ watts instead of 30 watts.

 

L1310416.JPG

 

But now we have another problem - the EP-R6 requires 24 volts, not the 50 volts now being provided. So the first order of business is a gigabit POE splitter so the data can be separated from the power.

 

[EDIT]: Previously I posted this story using a POE splitter that only handled power on 2 pairs. Since the AirFiber POE uses 4-pair POE we need a matching 4-pair POE splitter to take full advantage of the higher voltage. This one from Tycon should do the trick:

 

http://tycononline.com/POE-INJ-1000-DINx-Gigabit-Hi-Power-POE-InserterSplitter-Shielded_p_253.html

 

The AirFiber POE uses 3,6,7,8 for the negative and 1,2,4,5 for the positive, while this Tycon splitter uses 1,2,7,8 for negative and 3,4,5,6 for the positive. To correct this difference simply use a crossover cable between the POE supply output and the POE splitter input.

 

Now that we have a way to separate the power, we need a voltage reducer to take it back down to the 24 volts that the EP-R6 needs. I found this converter that takes 28-60 volts in and coverts it down to 24 volts out at 3 amps maximum, which is conveniently the exact same paramaters of the EP-R6 (24 volts, 3 amps):

 

L1310401.JPGL1310400.JPG

 

Any down-converter with the appropriate specs should work here. This particular converter can be found here:

https://www.amazon.com/gp/product/B00XKL6M8U

 

Now it's time to give it a little test drive using the blue crossover cable, and bingo - 24.3 volts:

 

 L1310526.JPG

 

 

 

 And now to power the EP-R6:

 

L1310527.JPG

 

It works! The EP-R6 is now powered with up to ~60 watts using a POE supply and Ethernet cable to extend power out to the EP-R6. This is enough to power an AirMax radio on all 5 of the POE outputs on the EP-R6.

Comments
by
‎08-07-2017 03:59 PM - edited ‎08-07-2017 04:39 PM

 

This is now the go-to story for anyone who posts:

 

- ER-6 randomly rebooting OR

- ER-6 randomly power cycles one or more radios.

 

Well done :-)

by
on ‎08-07-2017 05:06 PM

Had a request to provide links for the POE splitter and the step-down converter:

 

POE Splitter:

https://www.amazon.com/gp/product/B00ENNUWO4

 

Step-down converter:

https://www.amazon.com/gp/product/B00XKL6M8U

 

There are many different variations and models of splitters and step-down converters - any of them with the correct specs should work the same as the ones I used.

by
on ‎08-08-2017 06:54 AM

Nice job!

by
on ‎08-08-2017 07:26 AM

The only issue is its titled "Powering 3 or more radios on EP-R6 using only POE" but you used a poe, splitter, and a stepdown converter.
At the end of the day, a Netonix solution is less of a fire hazard. As a huge fan of ubnt, they need a little extra magic to make the EP-R6 more capable of realistic tower deployments instead of turning it into a network frankenstein switch. This is a great work around, but you couldn't deploy this in a major WISP.

by
‎08-08-2017 08:26 AM - edited ‎08-08-2017 08:27 AM

Using only POE up to the EP-R6, which was the major constraining factor. Not sure it's any more of a fire hazard than stock setup. At stock the POE brick was being maxed out (actually over-drawn) and there were 1.25 amps on the Ethernet cable. This solution the POE brick is at a comfortable 50% of capacity and there are only ~0.6 amps on the Ethernet cable. With so little current the step-down converter doesn't even get warm.

 

For larger scale use I would hope a WISP is using one of the EP-R6's bigger brothers anyway. We only use these for small jobs like one-off relays.

by
on ‎08-10-2017 09:37 AM

nice article, I just use a phoenix contact and im good to go.