Basement Grounding

[KC8JPZ]

Looking for anyone who may have installed a ground rod in a basement before. I am moving into my first house this weekend and was concerned about the grounding situation. What I am thinking about doing is drilling a hole slightly larger than the ground rod in the corner of my basement slab and installing the rod through that and finnaly sealing around the ground rod and concrete with an epoxy. I am pretty sure that water is not much of an isuue here. I was in the house after about 3 inches of rain and the sump was dry.I also noticed that there is no concrete in the bottom of the sump. Just gravel.Im about 20 feet from cold water pipes and don't want to run my ground horizontaly for that distance. Just curious to see any other ideas..

 

[jack103]

all grounds must be tied together per NATIONAL ELECTRICAL CODE if your house were to take a hit ,youre insurance company will send in an investigator so if vany electrical installations are not up to code this gives the insurance co a excuse to reneg on your policy,I have seen this happen.

 

[KC8JPZ]

Very good point jack. I do recall reading about this now.Looks like I may just be better off running the ground to something down there in the basement. I plan on grounding the coax where it enters the house. At that point, it's only about 4 feet from the breaker panel. I am running 3 lines total at that point.( 7/8" Eupen cable w/ground kits) Most likely running a couple more half inch andrew lines to the attic.

Thanks for the reply. Just want to be safe.

 

[BirkenVogt]

Find out where your electrical service is grounded to, usually it's right below the breaker panel. If that is the case then all you need to do is tie into the conductor going to the existing ground rod with a splitbolt or add another clamp to it, etc. That way you get a good ground without excess hassle and it is all tied together per NEC. I would not worry about any additional grounding unless you have a tower on top of a hill, grounding the coax at the point of entry you describe will provide plenty of equipment ground.

Birken

 

[kf4lne]

Run a peice of copper strap along the bottom of the floor joists over to the service entrance. Use that for a central grounding point, and tie it to ground on both ends. I picked up some copper water pipe being tossed from a remodelling job and a few couplers from the hardware store and i ran a copper pipe under the house from one end to the other, grounded it on both ends and ran a #4 copper wire to the service entrance ground. You ALWAYS want your grounds to be tied together, this helps to give lightning and static charges a place to go that isnt (you hope) your radios and keeps the voltage between grounds the same all around. its never good to plug your radio into an outlet and plug the coax in the radio and see smoke because of a voltage difference between the electrical ground and your antenna ground.

 

[ofd8001]

The following comes from the National Fire Protection Association about lighting protection:

"3.14 Common Grounding.
3.14.1 General.
All grounding media in or on a structure shall be interconnected to provide a common ground potential. This shall include lightning protection, electric service, telephone and antenna system grounds, as well as underground metallic piping systems. Underground metallic piping systems shall include water service, well casings located within 25 ft (7.6 m) of the structure, gas piping, underground conduits, underground liquefied petroleum gas piping systems, and so on. Interconnection to a gas line shall be made on the customer’s side of the meter. Main-size lightning conductors shall be used for interconnecting these grounding systems to the lightning protection system."

So in addition to attaching your antenna ground to the drive ground near your electrical panel or service entrance, you may also want to attach it to the cold (not hot) water pipes. (You don't use hot because if you have to replace the water heater, then while the old one is out and before the new one is in, you ain't got no ground).

 

[kf4lne]

And because of that requirement on well casings, I have a nearly 200 ft ground rod

 

[Yokoshibu]

And because of that requirement on well casings, I have a nearly 200 ft ground rod

as long as the lightning doesnt take a trip down the wires to the pump (if yours is inground) if not then your A OK!

but I never though of that.... another good benefit towards having a well!

 

[Viper43]

And because of that requirement on well casings, I have a nearly 200 ft ground rod

I have had to replace three well pumps in 3 years, my well goes to 180 feet, don't rely on it for grounding

JS

 

[LouisvilleScanMan]

Our breaker box is located in a concrete wall underground in the basement and accessed by a small wooden door, my station is also in the basement but about 20-25 ft away from the box. Could I run a length of 10 AGW wire from a copper grounding bus at my station to the central ground at the box or would that be too long?

 

[ka3jjz]

I have had to replace three well pumps in 3 years, my well goes to 180 feet, don't rely on it for grounding

JS

I don't understand why not; any one of them ought to make a terrific ground, even if the well has gone dry, there may well be enough soil conductivity at that depth to do the job. Even better if the three wells are relatively close together - bond them together and bond to that connection, and hoo boy you should be in ground heaven. Definitely something to consider.

73 Mike

 

[KC0QNB]

Of course this is dependent on the condition of the well casing and the material it is made of, case iron is a lousy conductor, steel pipe is not a real good conductor, especially if it has surface rust, pvc doesn't conduct at all. With all the variables encountered, and the fact that one of the main ideas of a lightning grounding system is to keep the lightning outside of the house, I wouldn't use a well casing as a ground rod.

 

[SCPD]

Water pipe

Looking for anyone who may have installed a ground rod in a basement before. I am moving into my first house this weekend and was concerned about the grounding situation. What I am thinking about doing is drilling a hole slightly larger than the ground rod in the corner of my basement slab and installing the rod through that and finnaly sealing around the ground rod and concrete with an epoxy. I am pretty sure that water is not much of an isuue here. I was in the house after about 3 inches of rain and the sump was dry.I also noticed that there is no concrete in the bottom of the sump. Just gravel.Im about 20 feet from cold water pipes and don't want to run my ground horizontaly for that distance. Just curious to see any other ideas..

Run the 20'. The cold water pipe is the best ground you can get. Better than a ground rod. Way better than using electrical ground.

 

[SCPD]

And I repeat myself (I do that sometimes)

Our breaker box is located in a concrete wall underground in the basement and accessed by a small wooden door, my station is also in the basement but about 20-25 ft away from the box. Could I run a length of 10 AGW wire from a copper grounding bus at my station to the central ground at the box or would that be too long?

Run about a 6 AWG cable to the cold water pipe. Don't use the ground in your distribution box, if a cold water pipe is available. If you don't have running water, do you have cable? Good chance they sank a ground rod outside when they installed. Go to it, but only IF you don't have city water. But the cold water pipe is the best ground you got in the house.

 

[Thayne]

I agree with Wyandotte.
Ground rods are not very good grounds; that is why some inspectors require 2 of them at least six feet apart; and also why the code says #6 copper is the biggest you need for any ground rod.

One time I saw a ground rod thru a sidewalk that took a good lightning hit; it even blew the sidewalk up for about 2 feet around the rod from the sudden steam being generated.

 

[tonsoffun]

Be careful with the cold waterlines as it states here:

Cold water pipes make poor grounds in most cases because the length of copper pipe to earth is often very long. Any lead over ten feet probably should be avoided for most applications. Additionally, pipes of this type connect through numerous solder-sweated joints, bends, and possibly even conversion to plastic pipe (a good insulator) before reaching ground. The fact that the pipe may have water inside is irrelevant. When such systems are used in transmitting service the piping becomes part of the radiating structure and ground level radiation will often be severe, causing interference to other services or neighbors.

My copper water lines at home are as described in that paragraph so be really sure you don't have that conversion from copper to plastic.

I have seen the cable companies ground there equipment on cold water lines not knowing it does that transition.

Hope this helps

 

[KC0QNB]

Be careful with the cold waterlines as it states here:

Cold water pipes make poor grounds in most cases because the length of copper pipe to earth is often very long. Any lead over ten feet probably should be avoided for most applications. Additionally, pipes of this type connect through numerous solder-sweated joints, bends, and possibly even conversion to plastic pipe (a good insulator) before reaching ground. The fact that the pipe may have water inside is irrelevant. When such systems are used in transmitting service the piping becomes part of the radiating structure and ground level radiation will often be severe, causing interference to other services or neighbors.

My copper water lines at home are as described in that paragraph so be really sure you don't have that conversion from copper to plastic.

I have seen the cable companies ground there equipment on cold water lines not knowing it does that transition.

Hope this helps

You did a better job explaining this than I could, +5 for posting

 

[Thayne]

The NEC requires that the connection to the cold water line be made within 5 feet of the entrance of the pipe. The copper buried coming into the house is always soft drawn and one length; The only grounding electrode that comes close is rebar in the foundation and most houses do not have it left accessible---

 

[prcguy]

I'm not sure if an indoor ground rod is a good idea, you don't want to invite lightning to dissipate inside your house. BTW, a friend of mine was minding his own business working near a window in his Green Mountain Falls, CO home and got struck by lightning WHILE IN HIS BASEMENT. He barely survived and it left him partially paralyzed. Follow the NEC code, ground the best you can but unless your house is designed from the ground up for lightning, you are not guaranteed to survive anything.
prcguy

 

[LouisvilleScanMan]

Well lucky (or maybe not) for me there isn't a window near my shack room but I guess the indoor rod idea is out the window (no pun intended). We do have cable tv but I don't know if they put in a ground rod but in any case the cable box outside (which I'm guessing it be near) is further then anything else from where I am.

We do have city water but the pipes are long and has several couplings and probably wouldn't work very well.

There is a window one room over (about 25 ft) from my station so I could put a rod in the ground outside the window but the wire length needed would be more then 30 ft and there would have to be some slight bends.The shortest route would be to drill right through the concrete wall next to my station and run a ground wire through there to a rod but it's not my house so that is NOT an option.

I don't know what to do.