Whole House Surge Suppressor & Lighting Strikes

Ground wire through the building is shorter than a buried wire around the building. I see no reason to believe the buried bond would adequately minimize the voltage between power and signal wires.

The NEC has a maximum length for the "ground" wire for phone and cable entry protectors [which may be too long].

If poor w could only read and think he could discover what the IEEE guide says in this example:

- A plug-in suppressor protects the TV1, connected to it.

- "To protect TV2, a second multiport protector located at TV2 is required."

- In the example a surge comes in on a cable service with the ground wire from cable entry ground block to the ground at the power service that is far too long. In that case the IEEE guide says "the only effective way of protecting the equipment is to use a multiport [plug-in] protector."

- w's favored power service suppressor would provide absolutely NO protection.

Cable-to-power wire voltage at TV2 without the suppressor is 10,000V; with plug-in suppressor at TV1 the voltage at TV2 is 8,000V.

It is simply a lie that the plug-in suppressor in the IEEE example damages the second TV.

For real science read the IEEE and NIST guides. Both say plug-in suppressors are effective.

Equipment damaged and house descriptions point to high voltage between power and signal wiring as the likely source of damage.

I would emphasize again that if you use a plug-in suppressor all interconnected equipment must connect to the same suppressor and all wires leaving the protected equipment (power, phone, cable, ...) must go through the suppressor.

A wireless router may be useful to reduce phone wire connections.

The furnace would normally be protected by the service panel suppressor. Would a plug-in suppressors add to that?

I believe dishes in general probably do not contribute much for surges (which is why the length of ground wire from entry protector to system ground is not limited by the NEC). But the earth potential 400' away may be far different from the potential at the house during a lightning event. And 400' can be a nice long wire antenna for nearby strikes.

You would probably have to protect power and all coaxes (in and out) at the switch. There are modular suppressors that have plug-in power suppressors that can be attached to other modules, like multiple cable modules.

You should have plenty of technical background. Look at how you protect all wires at all equipment, particularly if you can't get a short common bond at the entrances.

Separate the stat wires?

=================== Ignore Proteus. He is the resident troll.

(There is likely only one person that drives up the wall.)

For phone and cable, the NEC requires a ground wire from phone and cable entry protectors to the power grounding system (connection points include to the electrodes or grounding electrode conductor). The NEC requires the wire be 20 ft or less. But for 1 & 2 family dwellings it can longer if there is a grounding electrode (usually rod) near the entry protector, and a min #6 bond back to the power system ground. There is no max length ground wire for dish.

Tom and Jeff are probably well aware of the NEC requirements, but just for a common starting point.

Tom's method would earth all parts of the system, but I am not convinced that the external buried bond, which would also act as a ring ground, would be adequate to keep voltage on the power and signal wires close enough together. The #2 wire probably doesn't have a low enough impedance since the wire inductance (which dominates for surges) is not reduced a lot by larger size. Surge current to earth from surges on incoming power or signal would produce a voltage gradient along the wire. The bond wire length is longer than a bond wire through the house, so a question is whether the earthing effect is adequate to counteract the wire that is longer than the too-long wire through the house.

Another question I have is that during a near lightning strike the earth potential for points that are relatively close together can be far apart in voltage. For instance if lightning hits a near tree, the rod at the phone/cable entry may have a far different potential than the power earthing electrode. It is not obvious to me that the buried bond would adequately equalize the voltages. The IEEE guide has an illustration of a pad mounted A/C compressor/condenser that has a "ground" potential through the pad to earth that is far from the power system "ground" potential during a near lightning strike. The branch circuit "ground" wire has an impedance that is far too high to prevent the difference.

The IEEE guide says a 10 ft "ground" wire from phone entry protector to the ground at the power system may be too long. In the IEEE illustration (starting pdf page 40), with a surge coming in on cable and ground wire from entry protector to power system ground that is too long, the guide says "the only effective way of protecting the equipment is to use a multiport [plug-in] protector."

My alternative would be to earth the system as required by the NEC, then run the phone, cable, ... wires to the area of the power service, install a second set of entry protectors with short ground wires to the power system ground, and distribute from there. A few manufacturers (SquareD comes to mind) make service panel suppressors that include ports to run phone and cable (and dish?) wiring through the suppressor.

They are a decent electrode, as opposed to a ground rod that is a bit better than nothing.

Concrete encased electrodes have been required for most new construction since the 2002 (2005?) NEC.

Describes w perfectly.

The religious belief in earthing.

Plug-in suppressors are only "magic" to w. If he wasn't hampered by religious blinders he could find out how they work.

w's religious mantra protects him from disturbing thoughts (aka reality).

Still never seen - a source that agrees with w that plug-in suppressors are NOT effective.

And w never answers simple questions:

- Why do the only 2 examples of protection in the IEEE guide use plug-in suppressors?

- Why does the NIST guide says plug-in suppressors are "the easiest solution"?

- Why does the NIST guide say "One effective solution is to have the consumer install" a multiport plug-in suppressor?

- How would a service panel suppressor provide any protection in the IEEE example, pdf page 42?

- Why does the IEEE guide say for distant service points "the only effective way of protecting the equipment is to use a multiport [plug-in] protector"?

- And why aren't airplanes crashing every day - "a protector is only as effective as its earth ground"

For real science read the IEEE and NIST guides. Both say plug-in suppressors are effective.

I didn't know there was anyone left who hadn't killfiled proteus. He(she/it?) is the resident troll around here and has been for years.

Depends where you are. Here in the Northwest, our dark soggy soil is a pretty good conductor year round. Until recently, a single ground rod was considered adequate, now you have to have at least two. Never dealt with new construction though.

? "James Sweet" ?????? ??? ?????? news:h7i8g5$6a2$ snipped-for-privacy@news.eternal-september.org...

Here, in Greece, you have to have 3 on the points of an equilateral triangle with sides of 3 meters.

snipped-for-privacy@news.eternal-september.org...

Dimitrios Is that the requirement for a single family home in Greece? Have you seen any information on what the average ground impedance of that Grounding Electrode System is? I'm just interested in how it compares with what we measure here on our dual rod systems.

-- Tom Horne

?Grounding Electrode System is? I'm just interested in ?>how it compares

Yes, all 3 electrodes have to be connected with at least 10 mm^2 (#10) bare copper conductor, and the same conductor to the service (the meter) where neutral and earth are bounded together, usually in a 16 mm conduit, Conflex by

. I have not measured in the field the earth impendance, but in the college we did some measurements. IIRC the impendance was very small. (1-2 ohms). For a residence: #0 service, 3 X 10 mm^2 (#10) 1 X 35 A, single phase or 3 X 16 mm^2 (#8) 1 X

50 A, single phase, 230 V #1 service, 5 X 6 mm^2 (#12) 3 X 25 A, 400 V, three phase #2 service, 5 X 10 mm^2(#10) 3 X 35 A, 400 V. three phase.