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RcRaCk2k
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RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Sat Jun 07, 2014 3:15 pm

Hi all!

I've bought a RB260GSP to feed my Ubiquiti Hardware with passive PoE.

If i connect the Ubiquiti Hardware to the RB260GSP the Switch says "Short Circuit" and the red Led is blinking.

Is this Switch not able to PoE my Ubiquiti Device? The regular PoE-Adapter works fine.
 
imagica
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Re: RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Sat Jun 07, 2014 9:29 pm

In system enable "PoE over Long Cable" and check again it shud work.
 
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docmarius
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Re: RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Thu Jul 10, 2014 11:47 pm

My 260GSP works OK for Nanostation 5M, Nanostation 2, Rocket 5M, AirCam and UniFi LR APs, including 2 cascaded Nanostations.
What devices do you try to power and how are they arranged? Take care not to overstep 1 Amp/port.
 
taduikis
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Re: RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Thu Sep 11, 2014 9:38 pm

I had this same issue today. RB260GSP (FW v1.14) was powered over ~20 meters of 1 sq.mm wire via DC plug with 27.6V/2.4A PSU and threw "Short circuit" in PoE status no matter what settings were applied or what device connected. LEDs on RB I was trying to power-up kept blinking shortly with onboard speaker "ticking". Then I brought RB260GSP right to the PSU (eliminating the 20m power cable) and everything worked fine there. Checking "Port1 PoE in Long Cable" in System tab helped to resolve this problem, though power was supplied via DC port only :) This definitely needs some more documentation or mentioning in forums. The wiki explanation of what that Long cable setting does is also a bit sketchy.

The RB260GSP is a great product, but in my opinion needs a little more firmware refinement. For example PoE status messages are unclear or even misleading. Seeing "Short circuit" message we checked cables for shorts, tried different devices, etc. I don't know how powering circuitry on these switches work but it never works correctly out of the box for me. We shall try to connect some higher capacity capacitor in parallel tomorrow to absorb power spikes during device startups and see if it helps (without Port1 long cable setting).
 
Razaali1
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Re: RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Tue Sep 23, 2014 2:39 pm

I think this is possible using a jumper clip like that what you usually see in an internal hard disk. Make sure you place it in the correct orientation, or it might break your port. The jumper clip can be seen at the edge of a hard drive.
 
taduikis
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Re: RB260GSP / Passive PoE / Ubiquiti / Error: Short Circuit

Tue Oct 14, 2014 12:01 am

Btw, capacitor helps. It's not necessary to check "Long PoE cable on Port1" in my described setup when capacitor is connected just before RB260GSP.

Razaali1, I'm not sure what you're trying to refer here, but jumper idea is quite good to bypass short-circuit or overload protection. Honestly, I don't need it. We've been running RB250GS/RB260GS's with a bunch of Gigabit PoE's hanging before deploying GSP's and managed not to burn or overload anything for ages. This of course will not solve anything in already produced switches and MT probably won't do it due to warranty issues.. But oh well, just sayin' it out loud anyway..

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