House grounding

What would be the simplest way to ground my whole house from lightning and other electrical mishaps. Or how to tell if it already is.

Reply to
bigjcw1023
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Your electrical system is probably already grounded with rods and underground water pipe. If you're talking about lightning rods, that's a system of braided cables and rods that are placed on high points of the building with several runs into the ground. There is no simple way to do it

Reply to
RBM

There are three different things you could be talking about.

Lighting. While the basics are easy, the details are more complex and it is best to hire a professional. Things like the radius when turning a corner can make a difference that would mean it would or would not work in a lighting strike. If you are in a lighting prone area, the cost is well worth it.

Surge protection of electrical problems coming in or originating in the electric lines of your home. This protection comes in various types for different needs. For example I have whole house protection, but I also protect some of my more expensive and sensitive equipment with point source protection. Most newer equipment is less sensitive to the typical spike, but a really good one will do damage. Battery backup is also a good idea in many cases and may incorporate surge protection.

Grounding of wiring is required by code today and it should be in place for all but really old or some home brew (non-code) work.

If you can tell us a little more about exactly what you are looking for, maybe we can give you some more specific responses.

Reply to
Joseph Meehan

Excellent information on surges and surge suppression is available in a guide from the IEEE at:

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a simpler guide from the NIST at:
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The IEEE guide summarizes protection as: "1) Proper grounding and bonding, especially at the service entrance.

2) AC panel and primary signal surge protection at or near the service entrance. 3) Multi-port plug-in protectors near the equipment to be protected."

The grounding (connection to earth) in #1 for quite a while has included

1 or 2 ground rods and the water service pipe (if the pipe is at least 10 feet long buried metal). Recently a much better "concrete encased electrode" has replaced ground rods in new construction.

It is important that the phone, cable, ... entry protectors in #2 should be connected with *short* ground wires to the earthing wire at the power service.

According to NIST guide, US insurance information indicates equipment most frequently damaged by lightning is computers with a modem connection TVs, VCRs and similar equipment (presumably with cable TV connections). All can be damaged by high voltages between power and signal wires.

The multi-port plug-in suppressors in #3 may be useful for expensive high risk equipment. High risk equipment has both power and signal connections, like computer and TV with cable.

With plug-in suppressors, all interconnected equipment must be connected to the same plug-in suppressor, or interconnecting wires need to go through the suppressor. External connections, like phone & cable also need to go through the suppressor. Multiport suppressors are described in both guides.

If you are talking about direct hits to the house, they are very rare unless your house is very exposed, and as others have said require lightning rods. These are not likely a do-it-yourself project.

Reply to
bud--

"Grounding" doesn't do squat as far as lightning or surge protection.

To protect yourself from that which can go wrong with the electrical system, your best bet, probably, is "whole house surge protection." Such a device can be had for about $50 and attaches to the system at the circuit-breaker box.

Reply to
HeyBub

Lightning seeks earth ground. If conducted to earth via wrong paths, then you have damage. Which incoming paths are you trying to protect? 1) Lightning strike to your chimney? 2) Lightning strike to utility wires out on the street - a direct strike to household appliances? 3) Lightning that enters from earth ground on one side of the house, passes through household appliances destructively, then continues out other side of house back to earth?

Earthing for first above problem is called Franklin lightning rods. A rod properly installed above that chimney would connect lightning to earth without damage. Earthing provides chimney protection. Same protection for an antenna. That antenna must have its own dedicated connection to earth, or an earthed lightning rod protruding above that antenna. How effective is that protection? Quality of the earthing AND how that earthing connection is made determines whether lightning will earth via the lightning rod or will find a better earthing connectcion via something else.

A lightning strike to utility wires (second problem) means each wire entering a building must be earthed where wire enters the building. For example, one of three AC wires must be earthed directly to meet code - for human safety. Inspect that earthing. A bare copper 6 AWG wire must connect from breaker box to an earthing electrode that is best 'less than 10 feet' away. No sharp bends. Ground wire routed separated from other wires. No splices. Not inside metallic conduit. And not over the top of the foundation and down to an earthing electrode. That wire must be shorter and with less bends: directly through foundation and down to that earthing electrode.

Only some requirements are required by code for human safety - understood by all electricians. Some requirements for lightning protection must exceed code requirements - such as no sharp bends, separated from other wires, and 'less than 10 feet'. IOW that ground wire must meet code for human safety, and must exceed code to earth lightning (transistor safety)

To avoid the third problem, all incoming utilities must be earthed to same earthing electrode. IOW all utilities must enter the building at a same location. If your utilities are widely separated, then one solution uses a buried wire encircling the building so that all utilities connect to a common ground system:

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Even better is when that earthing electrode completely encircles the building or if an earthing electrode was installed when footings are poured (Ufer ground). Why do we install superior grounds? Because earthing defines quality of surge protection; a surge protector is only as effective as its earthing.

Solutions provided for three different lightning paths. Only component always required for surge protection is earth ground. Are both wires for telephone or the other two AC electric wires earthed? Ground those wires directly and get no electric or phone service. Earthing is provided by a 'whole house' protector. During a surge, those ungrounded phone wires are connected directly to earth by the protector. A surge dumped into earth via a 'whole house' protector will not wander inside the house seeking destructive paths through appliances.

Another with an agenda will say anything to avoid that fact. But his own citation says exactly what a protector does. On page 17 (of 24) in

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A very important point to keep in mind is that your

On page 6 (Adobe page 8 of 24):

The 'whole house' protector (when properly earthed) is so effective as to be used in all high reliability facilities. Responsible solutions don't waste money on ineffective solutions such as 'miracle' plug-in devices. That dedicated earthing wire is essential. Telco even installs an effective (earthed) protector on your telephone line, for free. Find the NID box (where their wires meet yours). Inside is a 'whole house' protector. But the protector is only as effective as its earth ground. Is a ground wire from the NID 'less than 10 feet' to the same earth ground used by cable and AC electric?

A protector does not stop or absorb lightning as some will claim. Surge energy must be shunted / diverted / connected / bonded / clamped to earth. Earth is where the energy is dissipated harmlessly. A protector is simply a connecting device to protection. Protection is the single point earth ground.

How do you verify your protection system? Follow those bare copper ground wires from breaker box to find the earthing electrode. Follow the TV cable before it enters to find a 'less than 10 feet' from cable to earth ground. Follow a green or gray wire from telco NID to that earthing electrode. This single point earth ground is a 'secondary' protection system.

Also inspect your 'primary' protection system:

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must install earthing especially at AC electric transformer. Just another earth ground essential to household protection.

Other grounding for human safety was described by volts500 in "Grounding Rod Info" on 12 July 2003 at:

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Reply to
w_tom

Not just the same electrode. The phone, cable, ... entrance protectors must connect with a *short* wire to the ground at the power service. Widely separated utility entrances can produce a high voltage between signal and power wires that can damage equipment connected to both. The IEEE guide provides an example starting pdf page 40. I see no reason to believe the schemes in w_?s link would significantly help. The IEEE guide says that if the utility entry points are distant "the only effective way of protecting the equipment is to use a multiport [plug-in] protector."

w_ has a religious belief (immune from challenge) that surge protection must use earthing. Thus in his view plug-in suppressors (which are not well earthed) can not possibly work. The IEEE guide explains plug-in suppressors work by CLAMPING the voltage on all wires (signal and power) to the common ground at the suppressor. Plug-in suppressors do not work primarily by earthing (or stopping or absorbing). The guide explains earthing occurs elsewhere. (Read the guide starting pdf page 40).

My only agenda is accurate information. That is why I posted links to reputable guides from the IEEE and NIST. Read them for yourself.

What does the NIST guide really say about plug-in suppressors? They are "the easiest solution". and: "Q - Will a surge protector installed at the service entrance be sufficient for the whole house? A - There are two answers to than question: Yes for one-link appliances, No for two-link appliances [equipment connected to power AND phone or CATV or....]. Since most homes today have some kind of two-link appliances, the prudent answer to the question would be NO - but that does not mean that a surge protector installed at the service entrance is useless."

Some of what w_ says is quite good. What he says about plug-in suppressors is nonsense. For reliable information on surge protection read the IEEE and/or NIST guides. Both say plug?in suppressors are effective.

Then read w_?s sources that say plug?in suppressors are NOT effective - oops - he doesn?t have any sources.

? bud--

Reply to
bud--

ok, after putting on a #4 ground to the outside rods AND to the plumbing inside, my local city inspector says the wire has to be in conduit anywhere it's in close contact with concrete. I totally missed this in the code. Can someone cite this for me? The reason i went with the #4 is because the book said it didnt' need conduit for physical protection. I never saw any mention of concrete or electrolisys.

thanks

Reply to
Steve Barker Garage

Actually I believe that is not exactly true. Point of entry protection can provide good protection (how good depends on the quality, which goes for all suppressors), but it can not provide protection from internal sources. So a problem in your home can damage equipment in your home.

Reply to
Joseph Meehan

Certainly possible, but I don't think there are many surge sources in houses that are likely to damage other equipment. Industrial buildings certainly have them.

Another surge source, pretty rare, is a very close lightning strike 'broadcasting' energy with interior wiring picking it up as a 'long wire' antenna or a 'loop' antenna. ('Loop antenna' would affect "two link appliances".)

Reply to
bud--

That one is what used to blow up computer networks. We ended up bodning machine frames together when the machines were having problems with "ground shifts" . Shunt that loop with a fat wire and it stops being able to blow through the onboard protection. In strip malls or strung out hotel/motel operations there can be a lot of difference between the EGC potential at opposite ends of the building in a lightning strike for a few hundred microseconds. We put torroids on the signal lines and made the shunt run as tight as we could. Fixed them

Reply to
gfretwell

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