Network cable buried without conduit – now doesn't work?

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I ran a 200 foot network cable between 2 buildings.

I did not use conduit. I wanted to see if it would be reliable without having to spend the money on conduit. It is in Canada so the frost goes down about 2 feet.

The cable was buried about 8 inches deep.

It worked last fall. It worked during the winter in

I ran a 200 foot network cable between 2 buildings.

I did not use conduit. I wanted to see if it would be reliable without having to spend the money on conduit. It is in Canada so the frost goes down about 2 feet.

The cable was buried about 8 inches deep.

It worked last fall. It worked during the winter in minute 20 degree temperatures. Now it is barely above the freezing mark and the cable stopped working. (no link lights on either end – I did all the usual debugging – the problem is the cable).

So my question. what is it that actually happens to the cable in a situation like that? Rocks move around as the frost comes and goes, and cuts it? Or what??

Best Answer:

SW: Could be any one of a lot of things really given those exceptional circumstances, but it is likely that either water has got into it and caused low electrical resistance between the wires or it has been squashed by water freezing and expanding causing the same problem.
I doubt that varmints such as mice would choose to live in frozen earth and eat plastic, for them there must be better options, like moving in with you for the winter.
Armoured cable is used by telephone companies without a duct, or conduit as you call it, and if it does ever go faulty then there are ways of measuring the position of the fault to the nearest yard so that you will only have to dig one hole to find and fix the fault with a splice without replacing the entire cable.
One would assume that if you ran the cable through a duct then you could use the old cable to draw in a new one, but if your duct is full of frozen water then that is not possible until it thaws out.
I also have personal experience with a ducted telephone cable where the water in the duct froze, expanded, and squashed the cable causing it to cease to function.
Eight inches is the depth of a spade so damage can occur, it needs to be deeper than that really, fourteen inches minimum is used by cable television companies for that reason.
Anyway mate, it`s duff now so cut your costs and abandon it and try something else such an overhead ( ariel ) cable on poles or along hedge tops or whatever is available, this will prevent most frost / water damage but not damage from strong winds.
Regards, Bob UK.

Other answer:

SW:
Was it rated as direct burial cable? If not, then frost/moisture/acids from the earth, etc. go to it. I suspect water got into the cable, and that affects the performance of the cable.
You MUST use outdoor rated/burial cable if you are not using a conduit.
Also, with frost, the ground may heave (more in the spring as the thaw comes about), and any sharp angles may cause the cable to stretch to a breaking point.
And like others point out, mice/voles/etc. like to chew on soft plastic jackets because they are made from oil products…
efflandt:
I find it difficult to believe that your frost line only goes down 2 feet unless you get so much snow cover that it insulates the ground. Occasionally water lines have frozen as deep as 8 feet underground in northern Michigan (south of Lake Superior). If the cable was only 8 inches underground it very likely got stressed from frost heaving.
Who:
There are a lot of idiots around tonight

get an ethernet cable tester (they are cheap on ebay)
you plug the tester in one end of the cable and a stub in the other end
press the test and it will tell you if the cable is ok or not, and if not what connection is at fault

(I know you said "I did the usual debugging" – forget it – most so called debugging procedures are useless at actually finding faults)

David E:
I am one that recommends you use conduit. If you don't, then use something like this http://www.amazon.com/Outdoor-Waterproof… designed for burying. Since it doesn't work, You gonna need to replace it.
Richard:
Without digging it up and examining it, there is no way of knowing. My guess would be that the sheath cracked and water got in affecting its electrical characteristics.
mike:
you need to dig it up and replace it cause unprotected cat 5 or cat 6 will break down with out being protected
SailorDumb:
mice like to chew though things when they're underground trying to stay warm.
Owen:
it broke

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