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2 Oldcrabs
01-07-2013, 08:03 AM
I just found out that TV does not install a "driven ground" for the panel box. They are "bonding" the reinforcement rods in the foundation and using this for the panel box ground. The electrician told me it is acceptable in Sumter County. The rods are about 6 inches off the ground, inside the concrete. A good ground would be 25 ohms or less. I did not know concrete was a good conductor. In the Mid Atlantic states there needs to be a seperate ground rod at least 8 foot driven. I do see the need to bond & ground the reinforcement rod, but they need to also install a seperate driven in the "Lightning Capital of the US". Heading to Home Depot to install my own.:rant-rave:

mulligan
01-07-2013, 08:13 AM
Found to be a waste of time/effort/money with the makeup of the soil here. Connection from the ground rod to perimeter grid of re-bar much more effective.

jimbo2012
01-07-2013, 08:31 AM
Interesting, but then if you install lightning rods which are supposed to connect to ground rods how would that work??

2 Oldcrabs
01-07-2013, 08:34 AM
Found to be a waste of time/effort/money with the makeup of the soil here. Connection from the ground rod to perimeter grid of re-bar much more effective.

If that is the case, why do they drive ground rods for lightning protection? Cost of ground rod, rod connector and # 4 copper, less than $30?

DonH57
01-07-2013, 09:09 AM
I find that really odd to be an acceptable grounding point. Properly placed reinforcing rebar in concrete are placed not to contact ground.

mulligan
01-07-2013, 09:46 AM
To be truly effective, the driven ground rod needs to contact bedrock (we have none), ground water, or at minimum damp soil (possibly) testing in Florida has shown that the rod in contact with reenforcing steel to be most effective. This came from a licensed electrician ( like hen's teeth around here). Personally I would love to see a true megger test to see how really effective the ground system really is.

jimbo2012
01-07-2013, 10:51 AM
I think this article (http://ecmweb.com/site-files/ecmweb.com/files/archive/ecmweb.com/images/archive/0900groundrods.pdf) covers a lot of info

entemedor
01-07-2013, 06:22 PM
Kitty litter that says 'clumping' on the bag is made of bentonite.

Ooper
01-07-2013, 07:11 PM
The Ufer rod is used frequently here in Florida. Florida's soils generally do not hold moisture very well, but concrete does and this is where the Ufer ground rod is placed. Google "Ufer ground" or "Ufer rod" to find out more.

2 Oldcrabs
01-08-2013, 07:34 AM
Neighbor installed an Ham Radio antenna disguised as a flag pole. He used it before installing some type of equipment that induced a stray voltage into the ground. At least 14 homes around him tripped AFCI breakers, except for the one home that had installed his own driven ground. The homes closest to the antenna tripped the most breakers. The home with the driven ground was the 2nd closes to the antenna. It appears to me the driven ground was effective! We have no problem with neighbor and the flag pole looks like any other flag pole. With the homes being struck by lighting and the resulting house fires I will spend about $30 and install an extra ground.:posting:

CaptJohn
01-08-2013, 03:46 PM
I will spend about $30 and install an extra ground.:posting:
It certainly won't hurt and the more the merrier! :laugh:

PS. There is a much longer more scientific thread on here about rods if you do a search.

aljetmet
01-08-2013, 04:48 PM
Neighbor installed an Ham Radio antenna disguised as a flag pole. He used it before installing some type of equipment that induced a stray voltage into the ground. At least 14 homes around him tripped AFCI breakers, except for the one home that had installed his own driven ground. The homes closest to the antenna tripped the most breakers. The home with the driven ground was the 2nd closes to the antenna. It appears to me the driven ground was effective! We have no problem with neighbor and the flag pole looks like any other flag pole. With the homes being struck by lighting and the resulting house fires I will spend about $30 and install an extra ground.:posting:

So are you saying my $1,500 budget for a lighting rod is a bit much?

rubicon
01-08-2013, 05:03 PM
I unfortunately have to admit and ask someone to talk to me like I am a fourth grader because while I understand what a ground is my eyes glaze up after that point is made.

2 Oldcrabs
01-09-2013, 06:40 AM
So are you saying my $1,500 budget for a lighting rod is a bit much?

The ground rod I am talking about is for the electrical panel box. If you are having Lightning Protection installed on your roof, they will install several ground rods where the ground wire comes down from the roof. Just make sure they "meggar" the rods for 25ohms or less.

AeroEngRetired
01-25-2013, 10:20 AM
Please give me a moment to chime in here.

As far as code compliance, bonding to the electrical ground is all that is needed, however, here is the problem I have found.

1) When they come out to build out your house, the supplier takes the rebar and drops it in the yard. I have even seen it where it comes in rusted.

2) The rebar is tied together with metal twist-ties (note: rust on rust) limited to no continuity through out the house.

If you are on the marion side, they do use ground rods instead of rebar grounding. The problem with that is they use, "galvanized steel" rods. Which in about 10 years are about rusted out due to soil deterioration.

My solution is to install (in addition to rebar grounding) a COPPER CLAD stainless steel ground rod that is 5/8X8ft (with a #4 or #6 wire). Please make sure you locate your property for underground utilities.

If you do decide to get lightning protection. Make sure your installer grounds to the electrical, phone, and cable grounds. As if he did not, you have actually made your lightning protection system worst as you created more different electrical potentials. I also have to agree with the post above me that 25 OHMs or less is great grounding, but national code writers UL and NFPA do not state a actual number when it comes to OHMs to ground. Getting 25 OHMs to ground in the Villages (except where the lightning cable connects to the electric) is almost not possible unless living by the water or having great clay soil. I have been on projects where we had to sink ground rods up to 100ft to obtain 50 OHM's to ground.

AeroEngRetired
01-25-2013, 10:25 AM
So are you saying my $1,500 budget for a lighting rod is a bit much?

In no way. Installing a multi-ground rod system will protect you from a lightning strike (if installed correctly). Installing extra grounding will help ground out your meter and a big plus for surge protection devices inside the home.

Ooper
01-25-2013, 10:54 AM
Here is a link to the Ufer grounding system. It is commonly used in Floria or other sandy soil areas...
The Ufer Ground (http://www.psihq.com/iread/ufergrnd.htm)

gustavo
01-25-2013, 01:39 PM
The ground rod I am talking about is for the electrical panel box. If you are having Lightning Protection installed on your roof, they will install several ground rods where the ground wire comes down from the roof. Just make sure they "meggar" the rods for 25ohms or less.

A "megger" test is a term used for megohm meter test. It is used to measure the effectiveness of insulation when exposed to a high voltage, typically 500 volts. the 25 ohms or less resistance check would be done with a regular continuity tester or if looking for really low resistance a micro ohm meter.

2 Oldcrabs
01-26-2013, 07:58 AM
South of CR466a seems to have clay about 3' deep. 10 homes installed 5/8 x 8' copper clad ground rods. Neighbor is using Ham Radio and no one has tripped a breaker. TV grounding may meet the NEC code for the area, but it is not very effective!:(

Lightning
04-20-2013, 08:03 PM
The ufer grounding system is for electrical safety to prevent electrical shock - and is not designed to handle an indirect and certainly not a direct lightning strike. If lightning is your concern then you should have a lightning protection system installed by a UL listed installer. Door-to-door sales installers are not UL listed so you will have no idea if the system was installed to NFPA780, the national standard on lightning. Listed installers will drive a sufficient number of ground rods to the proper depth - usually 8 ft. copper clad rods (not rebar) 2 ft below grade beyond the drip line from the roof. In some cases they may need to go as deep as 30 ft. - but thats the installers problem - not yours.

graciegirl
04-21-2013, 12:08 AM
The ufer grounding system is for electrical safety to prevent electrical shock - and is not designed to handle an indirect and certainly not a direct lightning strike. If lightning is your concern then you should have a lightning protection system installed by a UL listed installer. Door-to-door sales installers are not UL listed so you will have no idea if the system was installed to NFPA780, the national standard on lightning. Listed installers will drive a sufficient number of ground rods to the proper depth - usually 8 ft. copper clad rods (not rebar) 2 ft below grade beyond the drip line from the roof. In some cases they may need to go as deep as 30 ft. - but thats the installers problem - not yours.

This man knows what he is talking about and he does not sell lightning protection and does not recommend anyone unless they are a UL listed installer..

He and his partner speak to groups here and he is an expert.

He has a column in the POA newsletter.

You can count on him for honest and helpful answers.

Fourpar
04-21-2013, 04:00 PM
This man knows what he is talking about and he does not sell lightning protection and does not recommend anyone unless they are a UL listed installer..

He and his partner speak to groups here and he is an expert.

He has a column in the POA newsletter.

You can count on him for honest and helpful answers.
...what Gracie said:BigApplause:

shcisamax
04-21-2013, 04:34 PM
We have a ham radio next door and breakers were tripping all day long. Finally, after reading on here that others installed grounding rods, we suggested that to the electrical company and were "poopooed" initially but eventually they actually put in a grounding rod. No more breakers breaking! That said, I have been told separately that it really doesn't do anything for lightening and you would have to put in a lot of them and very deep. And it isn't worth it.
I really do not understand anything about electricity and I don't want to.; I have to understand far too many other things. My brain's hard drive has just so much space and I try to prioritize what I really do need to know. So I am just repeating what I have been told and what I know works for our breakers issue.