I have a customer that did not label cables up to a rb800 on a tower. They are powering through the PoE port, and running data through another port on the rb800. We do not know which cable is which.



Question:

If you plug the passive PoE injector (48V) into a non POE port on the routerboard will it burn up the port?

Maybe yes, maybe no.

Take 48V PoE capable device, connect cable to PoE port and watch if it starts.

I guess I did not make this question clear so I will try again!!!

On a routerboard 800 - there is a port labeled PoE - this is where you plug the Ethernet cable that powers the board - The board is powered by a passive PoE power source?

There are two other ports on the RB800 that do not have the PoE label on them.

If you mistakenly plug the Ethernet cable providing power into one of the Non PoE ports - Will it damage the port?

Simple question: Can I please get an answer? PLEASE??????

Thanks!!

duplicate post

I guess I did not make this question clear so I will try again!!!

On a routerboard 800 - there is a port labeled PoE - this is where you plug the Ethernet cable that powers the board - The board is powered by a passive PoE power source?

Yes, either Passive or af compliant. Tip: http://routerboard.com is great to check these things.

There are two other ports on the RB800 that do not have the PoE label on them.

If you mistakenly plug the Ethernet cable providing power into one of the Non PoE ports - Will it damage the port?

Simple question: Can I please get an answer? PLEASE??????

Thanks!!

It shouldn't, but.... if it breaks, you keep both pieces.

Why don't you try all the cables on the POE port first? that way you'll know if they're carrying power or not before plugging them on the non POE ports...

I guess I did not make this question clear so I will try again!!!

On a routerboard 800 - there is a port labeled PoE - this is where you plug the Ethernet cable that powers the board - The board is powered by a passive PoE power source?

Yes, either Passive or af compliant. Tip: http://routerboard.com is great to check these things.

There are two other ports on the RB800 that do not have the PoE label on them.

If you mistakenly plug the Ethernet cable providing power into one of the Non PoE ports - Will it damage the port?

Simple question: Can I please get an answer? PLEASE??????

Thanks!!

It shouldn't, but.... if it breaks, you keep both pieces.

Why don't you try all the cables on the POE port first? that way you'll know if they're carrying power or not before plugging them on the non POE ports...

I would love to, problem is that there are two cables running to the unit - one for power, one for data, they are sealed at the unit and it is 300 feet in the air on a tower, down in the equipment shack all we have are two unlabeled Cat5e cables - they have no idea which one is plugged where.

My guess was to apply power to one, and plug the laptop into the other and see if it discovers. If it does not then swap the cables and try again. My fear was that if I applied power to the wrong port that it would burn it out and they would have to climb the tower - which costs them about 4K each time the have to send someone up.

No worries problem solved - I figured 50 50 chance so I had them hook it up and got it right the first guess - so it is up, configured and working and they did not have to climb the tower!

Thanks for all your help and I appreciate the response

Simple answer for other people looking for the answer to this question.

Plugging a passive POE injected UTP cable into a non passive POE port has a high chance of causing smoke, stink and non-functioning/broken equipment! Be ware.

I do have some equipment which released a bad smell a bit but survived without influenced performance or other issues. So you can get lucky. The only way to really test is putting the cable into a port which accepts passive POE as was mentioned here before.

Simple answer for other people looking for the answer to this question.

Plugging a passive POE injected UTP cable into a non passive POE port has a high chance of causing smoke, stink and non-functioning/broken equipment! Be ware.

I do have some equipment which released a bad smell a bit but survived without influenced performance or other issues. So you can get lucky. The only way to really test is putting the cable into a port which accepts passive POE as was mentioned here before.

Thanks Quindor - So my suspicion is correct - it will burn up a port - thanks again for confirming!

I would try to test it on the ground.
First: If RB800 costs circa 360$ in retail then it is worth to buy one to check it's behaviour and to not spend 4K$ on climbers.
Second: Why do you want apply full 48V ? Start from 10V. It lowers the chance of burning.

Maybe, you can try "intelligent" PoE source (802.3 af), that first checks connected devices if is PoE capable. For example some PoE smart switch. RB 600 works with them, I think RB 800 as well.