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JosephKK JosephKK is offline
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Default Sharing fixed problem with our telco lines

On Fri, 31 Oct 2014 12:55:14 -0600, bud-- wrote:

On 10/30/2014 11:46 PM, Michael A. Terrell wrote:

junebug1701 wrote:

On Thursday, October 30, 2014 8:20:06 AM UTC-5, Robert Macy wrote:
Actually, sharing with you all, but English, what can I say?


this started after the famous flooding here - covered in the national news.
PROBLEM:
outgoing calls: NO problem, clear voice line and dial up modem within 95%
of 'normal' [seen slower rates before with damp weather]
incoming calls: the ring sounded anemic, like a single tinkle, not to be
repeated. Pick up phone, and someone was there?! albeit the connection
sounded like old fashioned long distance.

This reminds me of a strange service call I had when I worked as a Bell System repair technician. It was a rural area and the customer complained that none of her phones would ring, but that she knew somebody was calling whenever her dog howled. Sounded crazy to me, but it turns out that she was on a party line which requires a good earth ground on the third (yellow) wire for the ringers. Well, the unlucky dog was chained to a poorly grounded water pipe which also held the ground clamp and wire for the telephone protector. Whenever she got a call the poor dog got a 90VAC jolt! That's one of the reasons the telcos quit grounding to water pipes in favor of the electrical power neutral.


(US practice.)

You mean the service "ground", not the neutral.

Phone techs had better not be connecting anything inside the service panel.

A convenient point of connection is the wire to the earthing electrodes,
but it is not the only place the connection can be made.

Recent services have an "intersystem bonding termination" where phone
and coax entry ground connections must be made.


The reason that they switched was that the NEC required them to. Some
fools couldn't tell the difference between a water and a gas pipe.


The NEC did not require them to.

Water pipes (10 or more ft of metal in contact with the earth) must
still be used as one of the power system earthing electrodes.


I don't know what version of NFPA 70 (NEC) you are talking about; but
recent editions of the NEC requires a grounding electrode (rod) with at
least 10 feet in direct earth contact; plus bonding to water pipe and gas
pipe when metallic. Also bonding to the structural steel if there is
significant steel above ground. Enforcing article 250 et seq. has been
part of my job for the past 8 years.


That metal water pipe can still be used as the ground for phone entry
protectors (if there is no intersystem bonding termination). In the past
the connection could be anywhere. Now it must be within the first 5 ft
inside the building. That is the same place the connection must now be
made for the water pipe as an earthing electrode.

Gas pipes are grounded at locations like furnaces.

Corrugated stainless steel tubing (CSST) is often used for gas piping
inside a building because it is flexible. There have been fires and
explosions, and I think all manufacturers now require the stuff to be
connected to the earthing system near the building entry. (There have
been fires where the stuff was grounded to manufacturer's specs. An
electrical inspector recommended electricians not make the ground
connection, then they will not be involved in the lawsuit. I would not
use CSST.)