Installing ground rods and other questions

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Old 08-13-20, 07:09 PM
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Installing ground rods and other questions

Ground at my house was set up many years ago, back when it was sufficient to ground (*or is it bond?) the panel ground/neutral to the water pipe close to where it enters the house from underground.

I'd like to update this to include two ground rods, specifically two 5/8" copper coated 8ft rods - these rods at Home Depot: https://www.homedepot.com/p/ERICO-5-...0UPC/202195738

In terms of driving them, I have a SDS+ rotary hammer drill, and I can get a SDS+ ground rod driver bit on ebay for ~$20. I just put it in hammer/chisel-only mode and go to town? Will this setup allow me to sink all 8ft of the rod, or do people usually have to resort to a sledgehammer at some point?

Any reason not to put the acorn on the rod before starting so that I don't have to grind down the peened head of the rod later?

*Does the bond to the water pipe serve two purposes - provide a path to ground for surges and also provide a low resistance path back to the poco neutral if a water pipe were to become energized?
 

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08-17-20, 08:10 PM
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Solid #6 bare is my standard operating procedure.
 
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Old 08-13-20, 07:11 PM
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FYI If the water line entering the house is metal the bond is still required at the entry point. That has not changed.
 
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Old 08-13-20, 07:24 PM
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Clamps on the rods before driving is customary as many inspectors look for the peened over ends as it indicates the rods were actually driven and not cut short.

How far the impact tool will install the rods is based on what's in the ground.
Unless you're in sand..... I wouldn't rule out the need for a sledge hammer.

 
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Old 08-14-20, 06:28 AM
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I Canada we are allowed to use a ground plate. Bury it 2 feet below finished grade. I think we only need one.


 
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Old 08-14-20, 07:22 AM
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Earth grounding electrodes have nothing to do with clearing fault current. They are strictly for diverting lightning strikes. Fault current is carried by the equipment ground back to the panel which is what trips the breaker. Current always goes back to the source via the wire not the earth.
 
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Old 08-15-20, 12:45 PM
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In terms of driving them, I have a SDS+ rotary hammer drill, and I can get a SDS+ ground rod driver bit on ebay for ~$20. I just put it in hammer/chisel-only mode and go to town? Will this setup allow me to sink all 8ft of the rod, or do people usually have to resort to a sledgehammer at some point?
Been a few years since I personally installed a ground rod, but the SDS hammer and ground rod driver is definitely the way to go. What we used to do was to dig a hole maybe 8" to 10" deep and drive the rod in the center of the hole as far down as possible. Attach the Grounding Electrode Conductor and you are ready for inspection. After inspection, fill the hole covering the top of the rod/clamp and the GEC. Ground rods and wire play havoc with lawnmowers and weedeaters.
 
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Old 08-15-20, 06:34 PM
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The water pipe ground is typically the primary grounding electrode and the ground rod(s) is the supplemental grounding electrode.

I have beat in my share of 8' ground rods using a 2lb sledgehammer. It works just fine as long as you don't hit anything. Now I use a hammer drill.
 
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Old 08-17-20, 10:11 AM
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OK, so the plan is 2 8ft ground rods fully sunk at least 6ft apart.

I'll use #6 copper wire, one continuous length from the panel to both rods.

1. Does the wire have to be solid or stranded? Does it have to be bare or insulated? If no requirements on either, is there a reason to prefer solid vs stranded or bare vs insulated?

2. Is there a minimum burial depth for this grounding electrode conductor? Or is a couple of inches below grade just to keep it from being disturbed by feet, lawnmowers, etc., sufficient?

3. I'll drill a hole through concrete basement wall to exterior (hole will be above ground) for the GEC. Does the wire need to be in any conduit as it runs through hole or along exterior wall as the wire runs into the ground, or in the ground itself?

4. Lots of choices of ground clamps at Home Depot. Seems like this should work for 5/8" ground rod, #6 wire and direct burial, but just wanted to confirm, thanks: https://www.homedepot.com/p/Blackbur...1-30/202907599
 
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Old 08-17-20, 12:01 PM
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Your link shows an acorn for 1/2" rod, but they have these for 5/8" as well.
Insulated wire will be harder to deal with, and typically not used for this job.
 
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Old 08-17-20, 01:25 PM
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That particular acorn is for 1/2" or 5/8".
"The Blackburn 1/2 in. and 5/8 in. Ground Rod Clamp is made of high-strength corrosion-resistant copper alloy. UL listed for direct burial, this ground clamp offers a hex-shaped dead bolt for 4 Stranded/10 Solid wire."

OK, I'll go with bare wire, and since I don't see any reason to use stranded, I'll use solid.
 
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Old 08-17-20, 08:10 PM
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Solid #6 bare is my standard operating procedure.
 
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Old 08-17-20, 08:26 PM
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Stranded wire is a bit easier to work with, but nothing wrong with using solid wire.

If you want to save some money, you can drive ground rod with 3lb sledge hammer if you have one already. Larger hammer will be harder to use because you will have to hold rod with one hand and have to use hammer with another.
Usually it goes easy halfway, and gets hard to drive rest of the way.

If you have underground utilities running where you plan on driving ground rods, have miss utility mark utilities to avoid any accident.
 
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Old 08-18-20, 01:58 PM
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I've got a 3lb mini-sledge I can use if the rotary hammer drill and ground rod driver bit doesn't get 'er done.

Yeah, I called 811 and am having the underground lines marked. Wish they could mark sprinkler lines!

At the 3:39 mark in this video, the electrician grounds the meter pan. He also runs the GEC in conduit to the meter pan.
https://www.youtube.com/watch?v=LuEAVdpny2U

Is this necessary? Why not run GEC from the panel to the ground rods? And why use conduit for the GEC?

Also, how does surge current from an inside-the-house surge get to the meter pan and ground rods, since only 2 hots and a neutral run from meter pan to main panel?
 
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Old 08-18-20, 02:42 PM
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2014 Code Language:

250.64(B)

A 6 AWG grounding electrode conductor that is free from exposure to physical damage shall be permitted to be run along the surface of the building construction without metal covering or protection if it is securely fastened to the construction; otherwise, it shall be protected in rigid metal conduit RMC, intermediate metal conduit (IMC), rigid polyvinyl chloride conduit (PVC), reinforced thermosetting resin conduit (RTRC), electrical metallic tubing EMT, or cable armor. Grounding electrode conductors smaller than 6 AWG shall be protected in (RMC), IMC, PVC, RTRC, (EMT), or cable armor.

I suspect weed wacker use in the area means it is exposed to physical damage.
 
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Old 08-18-20, 02:46 PM
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The GEC can be either from the main panel or the meter socket because the neutral is bonded to ground. The conduit was added extra protection and is normally not needed. Also remember what I said in post #5.
 
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Old 08-18-20, 03:47 PM
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The GEC can be either from the main panel or the meter socket because the neutral is bonded to ground. The conduit was added extra protection and is normally not needed. Also remember what I said in post #5.
Ah, the neutral-ground bond strikes again. One of these days that concept will be deeply embedded in my brain. Speaking of, I've got the green bonding screw installed on the main panel (Square D Homeline 100 amp plug-on neutral panel). I've got all the neutral wires on the neutral bus bars on either side of the panel, and an added ground bar at the bottom where all the grounds land. As I understand it, the ground bar is bonded to the panel by way of the screw securing it to panel. And the neutral bus bars are bonded to the panel by way of the green bonding screw. So if I understand that correctly, the ground and neutral bars are bonded by just two screws. It couldn't hurt, and maybe help(?), to have a copper wire run from the ground bar to one of the neutral bus bars?

Yep on post #5. The ground rods are there just for surges, not faults in the house wiring or equipment wiring - that's handled by the neutral-ground bond at the main panel.
 
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Old 08-18-20, 05:14 PM
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Installing a jumper wire connecting the neutral bar to the ground bar is totally unnecessary.
 
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Old 08-18-20, 07:54 PM
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Installing a jumper wire connecting the neutral bar to the ground bar is totally unnecessary.
Without a jumper wire, I am relying on the one screw fastening the ground bar to the panel to carry any current on the equipment grounding conductors over to the panel (and from there it goes to the neutral bus), correct?

While the NEC doesn't require it, wouldn't it be better to have a jumper between ground bar and neutral bus? I'm thinking the jumper (let's say #6 solid copper) would provide less impedance than the path that includes ground bar ---> ground bar screw ---> sheet metal panel ---> green bonding screw ---> neutral bus. And the lower impedance path (ground bar ---> #6 solid copper jumper ---> neutral bus) means higher current and thus a quicker trip of the breaker. Is my reasoning flawed?
 
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Old 08-19-20, 04:25 PM
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Are meter pans bonded to the neutral wire?

Asking because the cable TV and internet providers have opted to bond their installations to the metal conduit carrying the SE cable from the meter to the hole in the house. That conduit doesn't run into the house, so the only thing it's connected to is the meter pan. And the metal conduit above the meter pan dead ends where the service cable runs out to weatherhead.



So it seems to me that unless the meter pan is bonded to the neutral wire, these bondings to the conduit aren't grounding the cable tv and internet installations.

Since I'm installing ground rods once the utilities markouts are completed, can I just replace these bonding wires with longer sections of bare copper wire and attach them using small acorn clamps to the GEC wire that will run from the main panel out to the ground rods?
 
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Old 08-19-20, 04:53 PM
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If you have underground utilities running where you plan on driving ground rods, have miss utility mark utilities to avoid any accident.
I could never stress enough how important this can be. I once sent a service truck to install a temporary service for a Christmas Tree sales lot on a parking lot of a large strip center and the electric service was to be installed on an island in the lot. Everything went well till the ground rod went through a water service line to an older closed building. On that huge parking lot, what are the odds that one 5/8" ground rod would hit a single 1" water line? I should have bought a powerball ticket that day. To make matters even worse, the local water utility couldn't find the shutoff at the street. In the end we had a plumbing contractor come in and dig up the line, freeze it and repair the line. This is why contractors carry insurance.
 
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Old 08-19-20, 04:54 PM
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Like threads combined................

Yes..... the neutral is bonded to the meter pan.

can I just replace these bonding wires with longer sections of bare copper wire and attach them using small acorn clamps to the GEC wire that will run from the main panel out to the ground rods?
Yes. If those wires had been in place..... the utilities would have connected to them.
 
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Old 08-21-20, 10:42 AM
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2014 Code Language:

250.64(B)

A 6 AWG grounding electrode conductor that is free from exposure to physical damage shall be permitted to be run along the surface of the building construction without metal covering or protection if it is securely fastened to the construction; otherwise, it shall be protected in rigid metal conduit RMC, intermediate metal conduit (IMC), rigid polyvinyl chloride conduit (PVC), reinforced thermosetting resin conduit (RTRC), electrical metallic tubing EMT, or cable armor. Grounding electrode conductors smaller than 6 AWG shall be protected in (RMC), IMC, PVC, RTRC, (EMT), or cable armor.

I suspect weed wacker use in the area means it is exposed to physical damage.
I think this exposed to physical damage clause in 250.64(B) nixes my idea of running bare copper wire down to the dirt, because even though I don't use a weedwhacker or lawnmower in this area, it's not inconceivable that someone would do so.

So I'm thinking drill 1/4" hole through wall, run #6 bare solid copper wire from panel to and through the hole (no conduit) to the exterior face of wall (this will be ~1.5-2ft off ground), then as wire turns down toward ground, run it inside Sch.80 PVC (since the way I'm reading it, Sch.40 wouldn't provide sufficient protection from physical damage). The PVC conduit would extend to a couple inches below grade, and from there run wire without conduit to the rods.

My argument for no conduit through bored hole and no connector into the PVC running down exterior wall is that the wire isn't exposed to physical damage there (and code allows 6 AWG or larger GEC not exposed to physical damage to be run without protection). The exposure to potential damage is closer to the ground (lawnmower, weedwhacker). This would spare me from having to drill a considerably larger hole than 1/4".

Does this make sense?
 
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Old 09-03-20, 03:14 PM
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So my initial plan was running a GEC from the main panel through the exterior wall and down to the ground rods.

But I noticed this screw on my meter pan. It's bonding a wire from an old cable connection to the meter pan.


Yes..... the neutral is bonded to the meter pan.
Since the neutral is bonded to the meter pan, that means meter pan is bonded to main panel. So instead of drilling a hole through the wall to run GEC from main panel to ground rods, couldn't I simply attach GEC to this bonding screw and run to ground rods? Same grounding effect without having to make a hole in the wall. Acceptable by code?

Of course I would keep the existing GEC that runs from main panel to water pipe entering house.
 

Last edited by PJmax; 09-05-20 at 09:59 AM. Reason: resized/labeled picture
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Old 09-03-20, 07:42 PM
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No. The GEC needs to terminate to the neutral bar of the main panel.
 
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Old 09-05-20, 08:59 AM
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I would suggest you go a step further and install an intersystem bonding bridge and get that cable ground wire off the meter socket.
Arlington | Intersystem Grounding Bridges
 
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Old 09-05-20, 10:02 AM
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In looking at your picture.... I added an arrow.

What's up with that connector ?
That looks like conduit into a rubber cable gland or it's conduit in the wrong sized connector or is it just the angle of the picture ?

Make sure it's sealed so water can't get in there.
 
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Old 09-05-20, 02:34 PM
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@PJmax - good eye - that's another issue I was going to raise - let me take some better pics of the service entrance situation from weatherhead on down (along with what an electrician told me about it) and start a separate thread on that.
 
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Old 09-07-20, 11:36 AM
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A 6 AWG grounding electrode conductor that is free from exposure to physical damage shall be permitted to be run along the surface of the building construction without metal covering or protection if it is securely fastened to the construction; otherwise, it shall be protected in rigid metal conduit RMC, intermediate metal conduit (IMC), rigid polyvinyl chloride conduit (PVC), reinforced thermosetting resin conduit (RTRC), electrical metallic tubing EMT, or cable armor.
Unless it has changed recently (I don't think it has) the GEC when installed in metallic conduit must be bonded to each end of that conduit.
 
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Old 09-07-20, 07:00 PM
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The bond would be required if a metallic sleeve is used. PVC is easier
 
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Old 09-12-20, 05:56 AM
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If you want to save some money, you can drive ground rod with 3lb sledge hammer if you have one already.
This turned out to be spot on. The hammer drill turned out to be worthless for this application. I ended up using my 3lb mini-sledge to do most of the driving, with a 8lb sledge mixed in just to change things up.

In terms of the GEC, I know it must be continuous between panel and both ground rods. But I thought I read somewhere that it does not need to be continuous with the GEC running to the water pipe, meaning I can have another ground wire running from panel to water pipe. Is that correct?
 
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Old 09-12-20, 10:36 AM
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In terms of the GEC, I know it must be continuous between panel and both ground rods.
Continuous to the first ground rod. A separate piece of the same size wire can be used to connect the two ground rods.

But I thought I read somewhere that it does not need to be continuous with the GEC running to the water pipe, meaning I can have another ground wire running from panel to water pipe. Is that correct?
That is correct
 
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Old 09-12-20, 01:05 PM
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I would suggest you go a step further and install an intersystem bonding bridge and get that cable ground wire off the meter socket.
Arlington | Intersystem Grounding Bridges
@CasualJoe why do you say that? It's grounded via the meter socket.

I've got a few low voltage systems I'm grounding inside the house, so I'm using an intersystem bonding bridge that fits into the knockout on the main panel that the GEC exits from. That's where I'm grounding ethernet surge protector, telephone line, and coax. Figured I'd leave the Verizon FIOS ground on the meter socket as it is now.
 
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Old 09-15-20, 03:38 PM
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@CasualJoe why do you say that? It's grounded via the meter socket.
Because they look like hell in my opinion. Using that style of grounding clamps, also my opinion, is just a half fast way of grounding the system. Intersystem bonding bridges were added to the code for a reason.
 
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Old 09-16-20, 12:30 PM
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Because they look like hell in my opinion.
I agree, but it's a huge upgrade from the way cable companies used to ground with a hose clamp around a outdoor faucet. Or the magical 'ground to nowhere'. I saw where a 12ga cable ground wire literally stuck into the dirt, like a whole 2 inches. Yea... I'm sure that works well...
 
 

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