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wiring issue

PostPosted: Tue Mar 20, 2018 1:09 pm
by kw123
had something weird last night:

I have 3 cables running from my "server room" up through the attic, to the outside wall under the roof, down the outside wall hidden inside a wall space, back inside into the first floor (erdgeschoss).

Everything worked fine until 4:21am and 4:28am last night when first one then the other cable and the connected devices went dark (= expired)
2 of the 3 cables stopped working. With a cable tester: one had 2 out of 8 cables bad the other 6 out of 8
Checked in the attic and outside: no visible "animal hunger" destruction = the cables all look fine, no destruction

I would understand one wire of the 8 in a cable going bad .. but that many within 6 minutes ..

And no thunderstorms , no loss of power .. very quiet night.

any ideas?

Karl

I have another cable run, but that will make all the switches sequential (= 5 switches between TV and router ).. kind of works right now but ...

Re: wiring issue

PostPosted: Tue Mar 20, 2018 2:03 pm
by FlyingDiver
There's something in the wall chewing on them.

Re: wiring issue

PostPosted: Tue Mar 20, 2018 2:05 pm
by FlyingDiver
Are they loose in the wall space? Can you use one of them to pull new cable(s) into place?

Re: wiring issue

PostPosted: Tue Mar 20, 2018 2:07 pm
by durosity
That’s truly bibarre.. three thoughts occur:

Is it a PoE switch? I once saw one melt a network cable when it’s power supply failed. Might be worth cutting open the cables when you’ve replaced them?

House moving/settling might’ve moved the wires slightly enough to crack them if they’d been in situ a long time?

The Domotica Spectre has haunted your house. If so expect your dimmers to be the next thing to go..


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wiring issue

PostPosted: Tue Mar 20, 2018 3:02 pm
by kw123
just thinking out loud..
The the main switch (24 port) has POE on these cables, but not the remote switches (8 port).

1. There is 1 meter hidden cable between server room and attic, pulled the cable out, no damage
2. 15 cm between outside wall and inside not checked
3. cable in the wall space from roof to downstairs not checked, but that is loosely pushed inside. but you never know.
4. replaced one of the connectors, same result

I am out for 3 weeks, and that is frustrating... will think about it during my whole trip.



I guess I will pull new ones when I am back back and add 2 spares (was team effort w wife , I in attic she downstairs pulling and we are still married .. taping and would have been a hit on youtube)

Karl

Re: wiring issue

PostPosted: Tue Mar 20, 2018 4:06 pm
by ELWOOD
Most times it's critters chewing on the cable insulation. An other posit;iity is when the cable has a D.C current running through it
and and it is getting wet you can start to get electro platting. Takes a long time but the anode is dissolved and its copper is plated to the cathode.
Eventually the anode wire dissolves completely

Elwood

Re: wiring issue

PostPosted: Tue Mar 20, 2018 4:14 pm
by siclark
ELWOOD wrote:
An other posit;iity is when the cable has a D.C current running through it
and and it is getting wet you can start to get electro platting. Takes a long time but the anode is dissolved and its copper is plated to the cathode.
Eventually the anode wire dissolves completely

Elwood


Makes me glad I spent a painful day wiring all my external cat6 that carries Poe to my cameras into metal conduit.


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Re: wiring issue

PostPosted: Tue Mar 20, 2018 4:38 pm
by durosity
Crikey i’ve never seen that happen before… hope that doesn’t happen to me.

Re: wiring issue

PostPosted: Tue Mar 20, 2018 6:38 pm
by kw123
connectors:
it worked for 5 months.... and yes I did crimp them personally, tested with a simple catx tester (dc test), and I replaced 2 of them after the failure, same result, dc test fails on 6 and 2 wires
will replace them and then do some testing

and thanks for your suggestions.. the resolution will have to wait 3 weeks

Re: wiring issue

PostPosted: Tue Mar 20, 2018 7:58 pm
by kw123
also checked my earthquake sensor (raspberry shake) .. no earthquake this morning . :)

Re: wiring issue

PostPosted: Tue Mar 20, 2018 9:20 pm
by kw123
cable is std 1000 ft box with cat 5 solid wires and yes there were some kinks in there , but both cables at the same time and more than 8 wires dying at the same time ??

anyway in 3 weeks I will ry to solve this mystery

and thanks to everyone for commenting

Karl

Re: wiring issue

PostPosted: Sat Apr 14, 2018 11:05 am
by kw123
just to close the loop ...

after I came home, I traced the cables outside and was ready to remove them ... I detected that the cables were torn at an edge close to the ground, some what hidden . BOTH cables!!
This must have been an animal chewing on the cables. ... may be it was an entrance into the house for it

Most other parts of the cables are inside a PVC pipe, just this part was not

Replaced one end of of the 2 cables (~10 feet) and reconnected with cat 5 connectors and it works again at 1 Gbit..

need to think about how to protect it . .. may be add silicone with wire mesh around it


Karl

Re: wiring issue

PostPosted: Sat Apr 14, 2018 5:45 pm
by kw123
thats a great suggestion, will get one from homedepot..

Thanks

Karl