Static Electricity on a vacant CAT5 line

[jakematic]

Ran across this in my saved list tonight from some years ago, and realized I forgot to post here.

Was at my tower site tonight during a thunderstorm. Kept hearing a snapping sound. Couldn't figure out where it was coming from.
I happened to be behind the rack & noticed what it was.
The run of wire is roughly 300' long & is literally connected to nothing.
Apparently was collecting, arcing over at the base & then draining off up top. I never seen this before.
A true refresher in physics & electrical theory LOL

https://www.youtube.com/watch?v=bzr349f380g


Also note soooo many things wrong with that cable and termination !

[sirhc]

SO this could be many things.

1) Static charge on the tower like you say but if the other end of the wire is floating (not plugged into a radio that bonds DC negative to chassis such as UBNT Rockets through SMA to antenna, MIMOSA connector, Cambium Connector, UBNT AFX, UBNT AF24 (if ground lug is hooked up), UBNT AF24HD) then I would question static.

2) ESD but same conditions apply as #1 above.

3) And this is my opinion, insufficient service grounds as when there is stormy conditions where the temperature drops there is a NEGATIVE charge in the atmosphere and then if the positive charge apposing the negative charge (Newton' s Law) is on the earth surface which is when you get ground strike lightening whereas heat lightening is when the positive charge is above the negative charge and people see lightening in the sky above the clouds that does not come down to the ground.

Anyway if there is a negative charge in the atmosphere around your tower and there is a positive charge on the ground below the tower and the service rods are insufficient then the electrical ground which I am sure is bonded to the rack the cable is arching to is trying to get to the ground in the sky.

You might think I am crazy but this is how it works and I have had sites like this with the same snap arch of electricity that adding new additional service ground rods too fixed the issue.

But yes it could be any of the above but my advice is add NEW electrical service rods to this site and of course always make sure they are bonded to the tower ground rods which would help all of the above anyway.

[jakematic]

Completely agree.

Not my tower, just a video I had seen and forgot about.
My tower experience is from the Long Lines days of TD-2 and L3 coax... so know exactly what you mean,

Hoping that it drives home all the things you always say about grounding.

[sirhc]

Completely agree.
Hoping that it drives home all the things you always say about grounding.

LOL - People simply just do not listen, well, some do but many more just do not understand that 2 differnt ground potentials means current will flow and current destroys equipment.

Ground current can be harmonics of the normal 50/60 Hz which means its frequency can be very high such as up to and in excess of 500 Hz which goes right through filter caps put there to stamp out noise such as FM broadcast noise then this current wrecks havoc on electronics. --> POOF --> RMA "claiming it just died or came DOA".

[sirhc]

My WISP just experienced 3 days of BIG storms in the past week with ZERO equipment loss but now that I say this I probably will jinx myself as we have storms forecast every day from now till whenever with the high day temps 80F to 90F and cooling by 10+ degrees rapidly at end of day = STORMS.

ADD 2 NEW/EXTRA GROUND RODS TO ELECTRICAL SERVICE
BOND SERVICE RODS TO TOWER RODS
INSPECT AND CLEAN ANNUALLY
NEVER RUN COPPER ETHERNET BETWEEN 2 DEVICES POWERED/BONDED BY/TO DIFFERENT PANELS (GROUND POTENTIALS)

ABOVE ALLOWS YOU TO REST EASIER DURING STORMS, I DO.

I mostly fear WIND damage to structures (towers mounts) these days.