cable theft alert system

[nyikaconrad]

need help with designing a cable theft alarm system which is gsm based....the system should send messages to predetermined phone numbers in the case of theft...and any other amazing features that could be added to the project

 

[horace1]

any idea of the technology that you will use to detect the cable theft?

 

[Audioguru]

All my electricity, street lights wires, telephone and cable TV cables are buried underground. I guess that is why people are not stealing the wires.
People here park their cars in their driveway but the cars are not stolen. Light bulbs on the outside of homes are not stolen.
Do they also steal water pipes in your country? Garbage cans too?

 

[Allen6502]

Not sure how the thieves steal electricity and cable TV cables. But 20 years ago, working in a telephone company as an Exchange technician, cable theft was a common news here when the price of aluminium and copper was very high.

Our Exchange has 40,000 lines capacity and there were 2 cables which had been cut twice. The cable was very long and 2/3 of it was underground before crossing the river. After the cable crossed the river using submarine cable, the remaining 1/3 length was overhead as it was only catering about 800 subscribers. The thief cut the portion which submerged from the river at the ferry point.

So our engineers designed a simple circuit out of op-amps or comparators. They used one of the pairs from the cable and short circuit it at the end of the cable. The circuit was able to detect 10 cable loops with 10 LEDs each indicating one cable. And the box was installed in our guide house as they work 24 hours in shifts. If the cable was cut (an open circuit was detected), one of the LEDs would light up and the security guard would alert our special team as well as the police.

This problem was later solved when fibre-optic cables were introduced into out cable network. There isn't much resale value for the glass in the cable.

Allen

 

[chuckey]

So what sort of cable ? what sort of network? (Voltage/current/distance/star/bus/). Arrangements of monitoring nodes?
Frank

 

[Mattylad]

Walk upto cable with axe, quick chop, drag cable off wall etc - weigh it in.

Very common.

You'd need some form of signalling I.E using a pair of wires or the loss of a signal etc to get this to work.
Or bury the cable deep