Is existing grounding at the meter box ok?

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Hello, I'm hoping someone can help me understand if the grounding for my house is adequate, room for improvement, or just plain wrong.
1) Meter box is grounded with ground wire and rod beneath it.
2) Three service cable 2/0 CU run to the main panel (two hots and a neutral.) (No ground wire) about 25 feet away.
3) The main panel 200amp is the first disconnect. The neutral and ground bars are bonded.
4) There is no other ground rod or ground wire to or from the main panel.

So I'm guessing that the neutral 2/0 cable between the panel and meter box would serve as the ground?

Is this good enough?

Would the grounding be improved if a separate ground and ground rod were added to main panel bonded ground/neutral bus bars in addition to the ground and ground rod at the meter box? Or can it only have a ground to ground rod in one and not both locations? Each of the grounding rods would be on different sides of the house.
I had the panel replaced and upgraded to 200 amp by licensed electrician about 5 years ago and this is how it was already configured. I did ask if it was properly grounded but was a little confused as its also a 1965 house, and we didn't rewire the entire house and bring everything up modern code.
The existing ground rod under the meter box is also 50 years old and under a concrete patio with the bare ground wire sticking up out of it, so not sure what condion its in. The electrictions said they would put a new one when they installed new 200 amp panel but didn't. Maybe they tested it? I have a multi meter but not sure if that would be sufficient to test the resistance.
Any insights or suggestions would be helpful with my planning and having work done. Does this seem like normal configuration and fine, or would adding reconfiguring be a good idea? Thanks!
 
Forgot to mention there is only some PVC conduit up the side of the house or the service cable between meter box and main panel, so conduit isn't used as a ground.
I'm just hoping for some general insights, if this is standard configuration, etc. Ideally it would have a disconnect box, and separate ground/nutral bars on main panel but won't be able to upgrade that for a while, but if adding another ground would help that could be done sooner.
 
There is definitely "room for improvement"
A single 50 year old ground rod is not likely to provide much of a ground. At the time of the original install there was likely a connection to an underground water line and that would still be required if the underground metallic water line is still in place.
I would want two ground rods at the meter as a minimum.
(Was the new install inspected ??.... Codes vary but a 25 ft run to an interior panel with no outside breaker is unusual)
 
augie47 said:
There is definitely "room for improvement"
A single 50 year old ground rod is not likely to provide much of a ground. At the time of the original install there was likely a connection to an underground water line and that would still be required if the underground metallic water line is still in place.
I would want two ground rods at the meter as a minimum.
(Was the new install inspected ??.... Codes vary but a 25 ft run to an interior panel with no outside breaker is unusual)
Click to expand...
Ok good to know there is room for improvement.
Could two new ground rods connected to the main panel provide adequate ground protection? And just leave the ground at the meter box as is for now? Two rods could be installed there but would need to drill through concrete patio and rods would stick up near back door entrance, so would be much easier to install them closer to the main panel and ground the main panel, if that would accomplish the same thing?
When the house was built in 1965 this is how it was configured. The panel 25 feet away from the meter. The old aluminum service cable ran along the floor of the storage space above the garage, held in place with 16d nails bent over, and cable had been walked on for over 40 years.
Five years ago a huge tree limb fell in a storm and ripped the outside meter off the side of the house, so had electrician install new meter, the power company disconnected and reconnected, he got a permit. Technically the entire house should have probably been rewired as that was a major repair. At that time I also had the main panel replaced, and new copper service cable.
When I asked about the grounding the electrocution responded that it would be way more expensive to go that route, and total rewire of the house, which was out of my budget at the time, so just let them install the new panel.
I've never had any trouble with the wiring. I installed GFCI and AFCI on all the circuits and only one tripped when a screw shorted it out, so it was working. But grounding still concerns me, and would like to make some improvement now if I could. I'm seeing a lot of diagrams where either the meter box is grounded or the main panel but not both. So just wondering if it ok to have both grounded to different ground rods, if that would provide adequate grounding for main panel and grounded appliances and such downstream? Thanks!
 
I was reviewing ground codes today in my NEC BOOK. If I remember correctly grounding to earth has its own benefits such as bonding.

Grounding the system to Earth Via a ground rod electrode limits maximum voltage that may be induced by lightning, utility surges and something else?

Since the above are less common, your majority of your protection comes from your ground fault path for short circuit protection. PROPER BONDING but NOT grounding (ground rod) Does this.

Proper bonding uses a wire or a conductor to connect metals encasing electrical equipment that are likely to become energized due to their proximity to live conductors if a fault were To occur. (All Exterior normally non conducting metals touch each other Such as outside boxes)

Then the metal connects to main panel which touches neutral only at this point so that fault current travels back here to complete a circuit And trip breaker for your safety.

Grounding does not do this so that’s why I say bonding and proper hookup in main panel Should be your biggest concern. Then comes grounding
 
Jpflex said:
I was reviewing ground codes today in my NEC BOOK. If I remember correctly grounding to earth has its own benefits such as bonding.

Grounding the system to Earth Via a ground rod electrode limits maximum voltage that may be induced by lightning, utility surges and something else?

Since the above are less common, your majority of your protection comes from your ground fault path for short circuit protection. PROPER BONDING but NOT grounding (ground rod) Does this.

Proper bonding uses a wire or a conductor to connect metals encasing electrical equipment that are likely to become energized due to their proximity to live conductors if a fault were To occur. (All Exterior normally non conducting metals touch each other Such as outside boxes)

Then the metal connects to main panel which touches neutral only at this point so that fault current travels back here to complete a circuit And trip breaker for your safety.

Grounding does not do this so that’s why I say bonding and proper hookup in main panel Should be your biggest concern. Then comes grounding
Click to expand...
It is boded at the main panel.
Forgot to mention there is some copper water pipes, but only a small ground wire was connected from an individual plug outlet to a copper pipe. I'm guessing this was a handyman add on for that one particular plug. The kitchen and bathrooms plugs were originally grounded. Most of the house has been rewired. Only the bedroom plugs are still the two prog no ground. Everyone said the wiring looked fine, copper and good insulation, but will finish replacing the last bit of old wiring at some point as the insurance coppany asked how old the wiring was.
Still not sure if it would be ok to just add another ground rod and connect to the main panel? And leave the ground and ground rod at the meter?
 
At one time running a conductor to a bonded water pipe was allowed for EG when a new receptacle was added. IDR when that was discontinued.

A service may be grounded at any point from point of attachment on in to the Service Disconnect. I would be inclined to update, two new rods, properly spaced at, the meter. One of our local POCOs require one at the meter. Might as well make it two and be done. Your AHJ may have additional input.
 
I think all the answers have been given and any more would be in the "DIY" area, which we can't do.
I would suggest to the OP to get a good electrician to look the service over. Could even buy a consult/safety permit and have the inspector check it out.
Good luck!
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