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  1. #21
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    Quote Originally Posted by thermite View Post
    Well.. in legacy 2W copper systems the Telco ground didn't just protect the NTE - it also had a "Day Job" so to speak.

    "Ground Start" to draw dialtone.

    Dialtone starts here when you draw current from line-to-line.... nothing much to do with ground, since the phone doesn't even HAVE a ground wire. Takes ONLY two to make it work.

    No idea what it does in far East, but probably about the same.

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  3. #22
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    Bill, The best thing to do is call the phone company and tell them about your situation. They will come out and install a new ground rod and rewire it. It's their responsibility to make sure their line/equipment is properly grounded to avoid a hazard to you. I repaired many missing/broken ground wire's over the years.

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  5. #23
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    Quote Originally Posted by JST View Post
    Dialtone starts here when you draw current from line-to-line.... nothing much to do with ground, since the phone doesn't even HAVE a ground wire. Takes ONLY two to make it work.

    No idea what it does in far East, but probably about the same.
    It works. Subscriber STE was(is?) generally 'loop start', P(A)BX ground-start.

    The old saw was "you can always loop-start a ground start pair, but not always ground-start a loop-start pair". So the default config for our 'autodialer' program - back when they were still needed for independent IDDD carriers at all - was loop-start. That covered PBX, PABX, 'key' and and Digital 'key' descendents that were unpredictable - even 'mixed' - just as well as small biz STE.

    That was the continental USA, BTW. Ma Bell legacy or otherwise.




    That said, ye'd best have good grounding per Telco spec, regardless.

    MOV's and such quite aside, newer solid-state gear is actually only a fraction as good as surviving near-miss spikes as iron, copper, and carbon revertive-pulse STE was 50 or 80 years ago.

    Not that I have to care, lo these many years now.

    I optimistically had the Verizon FioS crew remove the 5-pair copper - already fifteen years abandoned as I had gone over to GSM and Comcast...

    Didn't expect Verizon to cut their own damn fibre so many times that I'd eventually remove THAT and its NTE as well.

    With zero 'terrestrial' links, if it weren't for GSM and 4G I guess I'd technically be 'off network' altogether..

    I still keep the legacy copper network that runs all around in the walls of the house on the proper block and Earthed per spec though. Might want to sell the house someday.. rather than the ashes of it...



    Bill

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    If you go back to the Ma Bell days, some phones required a ground to ring. There was also a railroad PBX configuration that used ground signalling. I know this because a bought a pre-war phone and the wiring label was inside.

  7. #25
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    "but not always ground-start a loop-start pair"

    These days the central office has some pretty sophisticated trouble states.

    If you pass current from one of the pair to ground, it will put the line into a trouble state.
    If you draw more than a few microamps across the pair, it will put the line into a trouble state. (but not
    enough to indicate an off-hook state, that is)

  8. #26
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    Quote Originally Posted by jim rozen View Post
    "but not always ground-start a loop-start pair"

    These days the central office has some pretty sophisticated trouble states.

    If you pass current from one of the pair to ground, it will put the line into a trouble state.
    If you draw more than a few microamps across the pair, it will put the line into a trouble state. (but not
    enough to indicate an off-hook state, that is)
    Aye - they NEED(ed) 'em. Last two homes have had (in order) a 'loop extender', and 'long loop adapter'. Reason I eventually shed copper pairs outright.

    First one worked OK up 'til about 1988 with an RDX coupler for the ASR-33, global 'cable address' service as well as fax and voice.

    Second - '91 onward - proved no good atall for [A | D] SL service as far away from the CO as I was. Lowly V.34 was better.

    Most LEC's have been 'working at' ways of abandoning subscriber drop copper for a long time now, wot with cable, fibre, and now 4G and beyond having eaten the base they need to maintain it, let alone install new...

    Bill

  9. #27
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    We're lucky where we are in peekskill, close to the central office so DSL speeds are reasonable. We actually
    are wired up to an old lead cable with paper-insulated pairs that terminates at a junction block on a pole
    that sits right at the corner where four properties all meet. This pole is right at the back of
    my yard.

    This works pretty well until somebody else complains about bad service and they try to steal my pair to
    give to them, and the DSL signal drops out. This hasn't happened in several years though. The ISP we
    use has clout with verizon so they can force them fix problems when they crop up. I still cannot figure
    out why they changed us from one copper pair (the DSL and the POTS were together) to a dry pair and the
    POTS line. We pay for the one, but the cost of the dry pair is rolled up into the ISP charge, and that didn't
    increase when they made that change.

    Go figure. I couldn't get a straight answer from the line tech or the ISP folks.

  10. #28
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    Quote Originally Posted by rwbaldwin View Post
    The NEC requires the 'phone line' to be bonded to the power service grounding electrode by no more than 20 feet of wire. There is an exception that allows a separate communications ground rod to be used when this is not practical, but the communications ground rod must then be bonded to the building's power service grounding electrode.

    As with all things NEC, modifications are required to comply with the recent code revision.
    ---
    While this is an old question, I'd like to add my comments for those happening on this in the future.'

    The answer by rwbaldwin is the most correct answer. The NEC (national electrical code) provides the rules and is universally used by states and cities for laws.

    Communication (phone,cable TV, satellite dish) needs to be ground bonded to the electrical power system for human and electronics safety. Surges happen for many reasons. Even if direct lightening strike isn't likely, it can induce a surge.

    Why not contact your provider? For your own safety, learn the correct way it is to be done. At a friend's house the AT&T installer connected ground to the central air refrigerant line. While technically grounded it isn't an NEC approved place to ground. R-410A refrigerant is mildly flammable. Which is why it is not approved. And there was a water pipe with ground clamps not more than 7 feet away. Water system was properly bonded to the electrical breaker panel too.

    As an electrical engineer, I often had to explain proper grounding to plant electricians. People who are licensed and supposed to know the NEC. I argued with one for more than 20 minutes. I finally told him to go out and look at a transformer on a power pole for an example of proper grounding.

    So ... don't trust installers to do it according to code. Plus don't accept their sloppy workmanship. Cables and wires should be properly fastened so they can't be snagged. A broken ground wire is as good as no ground wire.

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  12. #29
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    Your ground is currently connected to a metal pipe. By code the metal pipe (both water and gas) are bonded to the electrical grounding device (ufer or rod). So, you will just be taking a more direct route by taking your telco ground directly to your ground rod. Its been a few years since I have had new service installed but AT&T here runs their wire to the ground rod and adds their own clamping device.

    I have never seen (on a residence) a separate ground for telephone.

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    Single point it to the ground rod. In the long run you'll probably be much happier not sharing the service ground earth wire. Sharing the rod is probably ok.

  14. #31
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    Quote Originally Posted by thermite View Post
    Well.. in legacy 2W copper systems the Telco ground didn't just protect the NTE - it also had a "Day Job" so to speak.

    "Ground Start" to draw dialtone.

    Ground start was for pay phones. 2w POTS lines drew dial tone on an off hook condition (short).


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