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Gigabit PoE Problem

Posted: Wed Aug 08, 2012 8:54 pm
by jazier
hello falks,
I have a problem that I would like to discuss with you.
I have a RB800 and 2 RB435G and a pair of RBGPOE.

1. When I power RB800 or RB435G via RBGPOE (Ether 1 port) the association rate with my computer is 100Mbps.
2. when I power routerboards with RBGPOE and I connect my computer to Ether 2 or Ether 3, the rate is 1Gbps.
3. when I use power jack (external power) for powering the routerboards, the issue is the same. If I connect to Ether 1 the rate is 100Mbps and when I connect to Ether 2 and 3, the rate is 1Gbps.
4. when I use power jack for powering the routerboars and I connect two RB435G via Ether1 the rate is 100Mbps.

I have tested with different long cables, with new cables, checked cables, etc, etc. RouterOS version is the last (I also tried with one old version)

So what do you think my dear friends? is it hardware issue?, the PoE port does not work in gigabit rate?, Thanks in advance for your answers and suggestions. :)

Re: Gigabit PoE Problem

Posted: Mon Aug 13, 2012 8:07 am
by normis
From the description, it looks like the Ether1 ports are damaged by lightning or something else. If you have warranty, you can send for inspection, but there is a high chance that this is ESD (lightning) damage, which warranty doesn't cover.

Here is a guide how to avoid such issues in the future:
http://wiki.mikrotik.com/wiki/Grounding

Re: Gigabit PoE Problem

Posted: Mon Aug 13, 2012 11:43 pm
by jazier
Thanks a lot, I will take that into consideration.

Re: Gigabit PoE Problem

Posted: Mon Aug 20, 2012 3:34 pm
by MichelePietravalle
From the description, it looks like the Ether1 ports are damaged by lightning or something else. If you have warranty, you can send for inspection, but there is a high chance that this is ESD (lightning) damage, which warranty doesn't cover.

Here is a guide how to avoid such issues in the future:
http://wiki.mikrotik.com/wiki/Grounding
hi normis,
i'm reading the info on the link, but i have a question:

"Method #1 (shielded cable + grounding of the device): "
But, if i will ground the cable AND the device, i make a RF loop, true?

Re: Gigabit PoE Problem

Posted: Mon Aug 20, 2012 3:37 pm
by normis
I suggest reading this topic as well: http://forum.mikrotik.com/viewtopic.php ... 54#p294654

Re: Gigabit PoE Problem

Posted: Tue Feb 26, 2013 5:21 pm
by honzam
Is there plan to make http://routerboard.com/RBGPOE
with shielding?

How to schielding 1Gbit routerboards, when we have only RBGPOE (non schielding)?

Re: Gigabit PoE Problem

Posted: Wed Feb 27, 2013 8:58 am
by normis
Is there plan to make http://routerboard.com/RBGPOE
with shielding?

How to schielding 1Gbit routerboards, when we have only RBGPOE (non schielding)?
They are shielded, I just checked. We will update the photo make it clearer to see.
gpoes.png

Re: Gigabit PoE Problem

Posted: Wed Feb 27, 2013 10:57 am
by honzam
Is there plan to make http://routerboard.com/RBGPOE
with shielding?

How to schielding 1Gbit routerboards, when we have only RBGPOE (non schielding)?
They are shielded, I just checked. We will update the photo make it clearer to see.
Ok, in this case we have old revision. Non schielded

Re: Gigabit PoE Problem

Posted: Thu May 23, 2013 9:09 pm
by Joddi
Hello Routerboard team,

we have problem with new (shielded) revision of gigabit PoE injectors:
http://routerboard.com/RBGPOE

We are using them in our PoPs, where we have common -48V DC voltage (standard telco PSU with + pole connected to ground).
The old version of RBGPOE hasn't any shielding over RJ connector and works fine for us providing 48V DC power directly to powered devices with gigabit ethernet ports.
The present version of RBGPOE has shield connected on both male/female RJ connectors, which is fine to protect powered devices, but the problem is: this ethernet shields are internally connected inside RBGPOE to minus pole of DC circuit, which we consider to be wrong.

If we use new (shielded) RBGPOE at our site we get short circuit from minus pole to shield at RBGPOE and then to plus pole of central PSU which is grounded according to telco standard.

Please can you consider to redesign RBGPOE in a such way there will be no connection from RJ shields to DC power at all? Just both RJ's shields should be connected together as they are now, but not to the DC jack.

The present design of RBGPOE can be dangerous to powered devices too, because it provides minus pole on RJ shielding which may or may not be expected at target powered devices (RBs etc.). Shielding shouldn't be connected to PSU, but only to the central ground point, which is in case of RBGPOE shielding at metal case of switch or similar device where the RJ male side of RBGPOE leads to.

Thanks

--
Joddi

Re: Gigabit PoE Problem

Posted: Fri May 24, 2013 2:08 pm
by normis
Thank you Joddi, we will consider these suggestions for the next manufacturing batch. I have forwarded your complaint to the responsible people. Thank you

Re: Gigabit PoE Problem

Posted: Sun Apr 06, 2014 10:06 pm
by Zapnologica
Silly Question, But i came across this post and found it quite interesting.

When you refere to grounding in the link http://wiki.mikrotik.com/wiki/Grounding.

Where do you actually connect the ground wires to?

Is connecting them to the earth on your houses electrical system right? Or does it actually have to be connected to a copper stake in the ground(dirt).

Re: Gigabit PoE Problem

Posted: Tue Apr 08, 2014 9:33 am
by janisk
connect to the ground wire on the electrical system. Just make sure that grounding is properly set up. Also, if you musth create new grounding, it would be beneficial to for all the electrical appliances to have proper grounding.