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Man electrocuted after urinating on track
On Tue, 22 Jul 2008 19:24:34 GMT, "Eddie Bellass"
wrote: Many years ago, when telephone lines were in very short supply, 'party lines' were common. A party line, officially known as 'shared service', meant 2 premises sharing the same pair of wires. Incoming calls to one or the other were separated by arranging the 75 volt AC bell ringing current to travel out via one or other of the pair of wires and return to the exchange via 'earth'. This required driving a metal spike into the ground and connecting the bell's return path via 3-strand bare copper wire. One day I was called to a farm which had reported their dog howling in distress every time the phone rang. We sometimes had a laugh at the wording of some customer's reports but I went down to the farm all the same. I asked the operator to ring me back and sure enough, the dog gave first a little yelp and then a painful howl. After a few trials I went out into the yard to see the dog repeating the cycle, peeing as it did so. This couldn't be a coincidence, nor was it. The farmer had secured his dog with a new steel chain fastened by an eyebolt to a flat steel bar spiked into the farmhouse wall. In doing so he had broken the earth wire for the telephone. Instead of the ringing current going to earth via the spike it was travelling through the chain and the dog. The tickling of the 16.333 cycle 75V AC made the dog pee and gave the return ringing current an even lower resistance path to earth via its bladder and its willie. Given such circumstances, wouldn't we all howl? ;-) Not so painful, but one day while I was doing my apprenticeship with PO telephones, we received a "Fault for Special Investigation" form for the local hairdressers. This was another installation using earthed ringing (plan 107 = 1 main telephone plus 1 switched extension at a different address) and the complaint was that it didn't work on Monday and Friday mornings. We turned up on one of the appropriate mornings and lo and behold it didn't work. Upon pulling out a few hardboard panels to trace the earth connection we found that the earth wire didn't go to any kind of proper earth connection but disappeared down the shop's drain which on the day following the weekend or early closing was dry and totally useless as a conductor. "Older viewers" might remember manual telephones. One of the early systems (Central Battery Signalling system No1 aka CBS1) also used an earthed bell circuit (the "clear" signal was given by earthing one side of the line via a low-resistance bell circuit) and in hot weather subscribers would occasionally be asked to go out and water the ground around the earth spike if they reported that their bell wasn't ringing. |
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