WS 12 250 DC port errors on 1 GB only Airfiber 5x

[jadkins@skynetky.com]

As the subject states we have about 12 of these switches in service all setup the same way

Samlex DC power supply with battery backup hooked to 200 amp hours of capacity. Each switch is properly grounded and properly wired. We are using the WS 12 250 DC.

All sites work well but one.

Connected at the site having issues are two Airfiber 5X units for a hop. I thought maybe my cables were bad so I replaced them today with double shielded 23 awg cat 6 cables. Same results as the tough cable.

When the air fibers are set in 1000mbps mode or auto the ports take errors like insane. We can only move about 1mbps of data when this happens. When I revert the setting back to 100mbps the ports run fine no errors. I have to make the setting change in both the air fibers and the switches to get connected. If I set the air fiber to 100mbps only the switch connects at half duplex 100mbps. Kinda odd behavior. Any ideals or insight here would be great. We have an great data rate on the radio and would like to take advantage of the speeds over 100mbps. I forgot to mention we tried other switch ports on the switch with the same results.

I can post any screen shots needed.

[sirhc]

My guess it is not the switch but radios, do you have radios to swap out, or swap the switch and see what happens.



Do you have the switch connected to batteries or power supply?

If you hook switch to power supply why not use the WS-12-DC which is cheaper and designed for that purpose?

The WS-12-250-DC is designed to hook directly to batteries as it can use 9V - 60V.



Is the AC service ground rods bonded to the tower ground rods?
Do you have a dedicated ground wire running up the tower to the radios and or radio mounts?

[jadkins@skynetky.com]

The switch is hooked to the power supply and once ac power is lost it automatically routes power to the output of the supply.

I bought these unit for the ability to run the battery's into the ground if need be. Some of these site are very hard to get to in the winter and power restoration takes a few days when it goes out.

I have tried swapping the affected unit and it is still doing the same behavior. I do not own this tower site, I lease so I am not sure what the ground situation is like on the tower its self. The equipment shack has a ground bus bar around the perimeter of the room we tapped on to it with our rack and also directly onto the switch. So everything is good in there.

I guess the next step is to go out and measure resistance from the tower to the ground bus inside. What is a good resistance reading? I think the tower grounding maybe the issue forcing my Ethernet drain wires as ground for the tower.

Their are no visible ground bonds on the tower the base of the tower is encased in concrete so unless the grounding was done there I suspect it has none.

Their is also a rack full of two way equipment in this building. Maybe their is a ground issue there too. It is driving me nuts trying to figure it out.

I am not sure how open the owner would be to doing the grounding and bonding as needed. I doubt he will invest in it.

[sirhc]

well not only the ground wire but the Ethernet wires as well as Most radios including UBNT bond DC negative to Earth Ground so of the Tower is not grounded and the tower is not bonded to the service ground then your Ethernet cables care the tower Earth Ground, Static, and ESD charges.

Also if you do not have a dedicated ground wire that is lower resistance and shorter path than the Ethernet cables you have issues.

A steel tower made up of many bolter sections that are poor electrical connections is a poor path to Earth Ground

Here are some good posts on grounding:
viewtopic.php?f=30&t=1816
viewtopic.php?f=30&t=188
viewtopic.php?f=30&t=1429
viewtopic.php?f=17&t=1786&start=30#p13447
https://community.ubnt.com/t5/airFiber/ ... rue#M31070