Can't get good ruling on phone line grounds

[Eigenvector]

CAT 4 was a placeholder so far as I know, it was never in use. CAT 3 I've only seen in 10 Mbit connections, old computer networks but still widely in use. I think CAT 2 was the same as CAT 4, basically just a placeholder. CAT 5 is 100 Mbit connection line, CAT 5e is 1,000 Mbit connection, CAT 6 is

1,000 Mbit, plus providing power capability. Really it's all the same cable, just better tolerances and quality - except CAT 6 which has additional pairs. ****That's how I know it. That's not the pedantic and/or exact definition, there are better descriptions of it out there. So if anyone chimes in looking for an argument I won't even bother - no trolling here please!****

Anyway the whole project is on hold until Seattle gets back to normal, I doubt the phone company has time to worry about my home re-wiring project at this time. Hell, the entire town of Issaquah is out of power, at least it was when I spoke to the local Lowe's guys - and Issaquah is a BIG town, not some podunk.

[Bud--]

The NEC says insulated, but not the most important issue. Minimum size #14, #10 is good.

The Ufer ground, it is really good. (Underground metal water pipes are good too, but likely farther away. Ground rods are better than nothing.) [With a Ufer ground you shouldn't need a rod.]

I believe the ground bar is not one of the allowable points of attachment in the NEC. And IMHO: It is better not to run the conductor in with power wiring. Through the ground bar requires an extra connection in the path to the grounding electrode.

-- bud--

[Eigenvector]

BTW, examples of the stellar job done on the phone lines

Looks like a pretty good ground connection to me, no corrosion and the connection is nice and tight. But that splice! Christ that's a bad job if I ever saw one.

[Jim Redelfs]

Thanks for taking the time to post such detail. I am more informed.

Yeah, so I've heard. Good luck to you folks. I kinda wonder if they'll (Qwest) ask or volunteers to help. Then again, "they" asked for volunteers for Katrina that never panned-out. Despite being one big, fat, happy company, we still seem to stay within the original states that comprised each of the three BOCs (Bell Operating Companies) prior to divestiture: Northwestern Bell, Mountain Bell and Pacific Northwest Bell. We'll see...

[Jim Redelfs]

That was NOT done by a telco employee: They wouldn't have the TIME (or desire to TAKE that much time) to do it like that. A trip back to the truck, if the tech had neglected to bring along the proper connectors to begin with, would be MUCH faster, nevermind BETTER.

[Eigenvector]

Yeah I didn't think it was done by a pro. More of the previous owner's bumblings. The verdigris on the copper wires is an especially nice touch!, as is the clipped phone cable left just hanging there rather than simply fixing it.

[w_tom]

Connection from phone, through wires, through pipes, etc is grossly more than 10 feet. It is make worse by pipe joints, wire junctions etc. It does not meet 1990 NEC earthing requirements. I suspect your connection to earth is well over 50 feet AND does not make that earthing connection directly. It would be a prescription for electronics damage.

There are a number of ways to fix this. But you may regard them as too much work. The amount of work not justified by the risk. This for the benefit of others who are at more risk to damage.

For example that phone line could be rerouted to enter at adjacent to AC electric. Or wire is routed inside building well separated from any other wire or pipe to first connect to a protector at earth electrode - and only then distributing phone service to the house. Another suggestion from a utility is demonstrated by bad, ugly, and good figures in:

There is no way around a short ground connection (lower impedance) and a common earthing electrode if electronics protection is desired.

[blueman]

We have Verizon FIOS which comes in on fiber optic cable. The ONI (optical network interface) uses power and I believe uses a grounded (3-prong) cord -- thus, it is no longer attached to a long exterior metal wire (i.e. think antenna) and seems analogous to any interior low voltage wiring system like an alarm.

So does this situation in which the interior telephone circuit is literally optically isolated does the code still require that the demarc be bonded directly to earth ground?

Interestingly - our gas company specifically WARNS against bonding the gas entrance to ground (and will remove it if they see it). I have heard that some gas companies purposely run a small current on the external gas pipe to prevent galvanic corrosion. In those cases, the internal piping (which often is grounded to appliance ground) is isolated from the street piping via a rubber gasket of sorts.

[w_tom]

Optical network interface electronics still connects to AC mains. AC electric is equivalent to an antenna connected to optican network electronics. That incoming wire must be earthed where it enter the building to protect optical network electronics..

FIOS installations appear to have some earthing. Cannot say why with certainty. But an optical cable has a conductive wire within it. A conductor so that undersground optical cable can be traced before excavating. Have observed something from optical cable connected to earthing. But I did not inquire as to what or why.

Some gas companies want > We have Verizon FIOS which comes in on fiber optic cable. The ONI

[blueman]

Agreed. That's why I have whole-house surge protection right at the meter box...

If that wire is connected to the chassis ground and if that in turn is connected to the ground prong in the plug, then it should be properly grounded (and surge protected) in the house. If that electrical signal is just hanging there isolated from my house wiring then there is not much I can do about it since I can't access it...

Agreed. I asked my utility and they said "DON'T BOND IT"...

[w_tom]

Wire has impedance. That impedance is irrelevant to 60 Hz AC electricity; grounding that is for human safety. That same ground wire has too many sharp bends, splices, and bundled with other wires. Impedance is excessively high for transient protection. Bundled with other wires, it may even induce transients on those other wires.

Earthing for electronics protection demands other precautions such as no wire splices, no sharp bends, not inside metallic conduit, separated from other wires, and especially short distance. AC wall receptacle safety ground violates principles required for earth ground.

However, when transients are earthed at a building entrance (ie the 'whole house' protector), then higher impedance of interior wiring adds to appliance protection. This separation and impedance is why better protected facilities put a protector at earth ground AND distant from protected electronics.

For earthing each utility in a residential dwelling, each utility should make a less than 10 foot earthing connection - that wire length is critical. Therefore utilities enter a building at a common location to have a short earthing connection to a common earthing electrode. For earthing (and low impedance), the ground connection must be short - and other factors.