 LazManPremium join:2003-03-26 canada | reply to sbrook
Re: Fairly powerful shock from touching green line One tester I used to work with, thought it was funny as HELL to start making 'test calls' on cables we weren't finished with. Nothing like banging your hands off the back of wire-wrap blocks as ring-current runs through you... But he got his... One day, managed to get him out into the field on a 'complex issue' - while he had a hand-full of pair, buddy at the next cross-box fired up the megger...
The tester realized that maybe he wasn't so funny after all.
Laz |
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 sbrookPremium,Mod join:2001-12-14 Ottawa kudos:4 | Yeah, hitting him with a megger is NOT a nice idea! |
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 joshbDon't sweat the small stuff.Premium join:2006-03-04 Calgary, AB | reply to LazMan How much extra voltage does a DSL connection add too the line? |
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 sbrookPremium,Mod join:2001-12-14 Ottawa kudos:4 Reviews:
·TekSavvy Cable
·Rogers Hi-Speed
| Nothing worth noting. The reason for a 48V connection for conventional telephones is now largely historical ... The network could be run on significantly lower voltages were it not for all the equipment designed for 48V supervisory currents and 60V+ ringing current.
Amongst other reasons, carbon microphones needed a significant bias current to work properly and with their inherent resistance, voltages over about 40V were required for reliability. Ringers needed 60V plus to make the bells work. The relays and selectors (uniselectors, and 2 motion selectors) in early strowger exchanges worked best with about 48V operating voltages to combine reliability and speed etc. Also, party line selection which was done by grounding a circuit may result in higher resistance completing the circuit.
DSL doesn' add much at all by comparison. |
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 LazManPremium join:2003-03-26 canada | reply to sbrook said by sbrook:Yeah, hitting him with a megger is NOT a nice idea! You're right - but he didn't seem to understand why we didn't see the humour in the test-call thing, until after the megger thing.... |
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 | reply to brassy Let me guess, you were working in sock feet on the concrete floor in the basement...the perfect ground 
Try wearing shoes next time...  |
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