WS-8-150-DC Light and fan on but no boot

[sgus360]

I recently got two of these units and installed one in the field and one on the shelf for backup.
The one in the field had suffered a power issues and half the ports stopped functioning. So I went to replace it with the backup.
It is on a 24v DC power source. It worked for about 2 hours and then the ports turned off. The power light stayed on and the fan is constant.

After futzing with it for about 30 minutes I put it back in the box and put the original one back in service since at least two of the ports I needed works.
I brought back the backup unit to the office and powered it back up, no joy. There is no response with the serial port either.

I've submitted a RMA request, but would like to see what others suggest.

[sirhc]

My first question would be is the tower ground rods BONDED to the electrical service ground rods?

You might also consider adding a NEW electrical service ground rod as they may be corroded and insufficient.


Here are some good posts on grounding:
http://forum.netonix.com/viewtopic.php? ... 279#p19279
http://forum.netonix.com/viewtopic.php?f=30&t=1816
http://forum.netonix.com/viewtopic.php?f=30&t=188
http://forum.netonix.com/viewtopic.php? ... =30#p13447
http://forum.netonix.com/viewtopic.php?f=30&t=1429

[sgus360]

It was grounded. I think it may have been a circulation fan in the box that shorted and caused the surge. Not 100% sure on that, but I disconnected the fan and will be replacing it.

[sirhc]

It was grounded. I think it may have been a circulation fan in the box that shorted and caused the surge. Not 100% sure on that, but I disconnected the fan and will be replacing it.

I understand you said it was grounded but was the tower ground rods BONDED to the electrical service ground rods by a heavy wire like #2 TIN or GREEN?

Just because the tower has ground rods and the electrical service has ground rods means NOTHING if they are not BONDED together as they are 2 differnt ground potentials and the ground current will try and flow across the Ethernet cable.

GROUND IS NOT GROUND UNLESS THEY ARE BONDED

[sgus360]

I do understand your line of questioning. This is a hard rock metal mine site that the electrical is all done by the electricians. Everything is grounded to a single ground and tested. This is not a coms tower. It is a wood utility pole that is used for surveillance.
Once this unit is fixed and I'm back in the field to replace, I will bring the electricians with me to triple check all the grounds.

I appreciate all your input.

[sirhc]

Keep in mind normal electricians (residential and commercial) are not familiar with telecom site grounding practices.

When the switch comes back from RMA we will be able to tell you what happened rather it was a failure or damage and what was the most common cause for the damage.

[sgus360]

That would be great! I'm always looking for way to improve.