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I just watched an episode of "Ask this old House" that had a licensed electrician upgrade a 100a service to 200a on a viewer's home. The segment was well done and thorough. He even used duct seal on the screws on the new box and in the penetration to the house siding and in the service mast pipe. I've never seen any electrician I've hired do that.

He made a point to note that the neutral and grounds must be bonded inside the service main, and the bonding screw tied the neutral bar to the panel case. He drove two rods under the meter socket at 6' apart and wired them together with a #6 copper wire which was set under a lug adjacent the neutral wire in the meter socket.

The meter socket was outside, and the service panel was inside the basement about 2' away. What puzzled me was that he took another ground wire from the neutral buss bar and bonded to the water line. It was copper. Why didn't he just go the 2' back out the wall and bond it to the ground rod?

I live in Texas. We don't have basements, and our water lines are plastic lines throughout my house, out to the water meter, and all the way back to the water supply facility. I've never seen a ground wire bonded to a water line around here. It just isn't done. I have seen grounds tied to gas pipes, however:eek:

Could he have run that second ground wire back outside to the ground rod instead?
 

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You bond panel to the cold water, so that if the copper does get energized, it will go back to earth ground. Inside breaker panel is bonded to meter pan through the Neutral, but meter pan is grounded by the ground wire to ground rod.. All of this is in the NEC, and what I just stated is the short version. BTW, stop watching Ask this old house. Worst than the crap that DIY shows on their regular shows.
 

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gregzoll said:
There have been too many instances of questionable unsafe practices shown on toh too many times.
Electrical only? Or other? I don't watch either enough to know...but what I have seen tells me that TOH certainly is way under target on electrical content, and Holmes thinks a common maple tree will electrocute you, unless he planted it.
 

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Discussion Starter #6
You bond panel to the cold water, so that if the copper does get energized, it will go back to earth ground. Inside breaker panel is bonded to meter pan through the Neutral, but meter pan is grounded by the ground wire to ground rod.. All of this is in the NEC, and what I just stated is the short version. BTW, stop watching Ask this old house. Worst than the crap that DIY shows on their regular shows.
Got it:thumbsup: It's not providing a ground path for the electric panel. It's providing a ground path for the water piping if the piping becomes energized.

If it is not being used as a grounding system described in NEC 250.53(D) and 250.68(C)(1) and a dwelling has copper pipe throughout the house, can a ground wire be connected at any convenient place to bond the pipe to the grounding system? The panel may be 20' from where the copper supply enters the house unable to bond the pipe within 5' of dwelling penetration as specified in 250.68(C)(1)

Don't be so hard on TOH. This segment was done by a professional licensed electrician.
 

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Graphics in this reply are from Mike Holt Enterprises

I just watched an episode of "Ask this old House" that had a licensed electrician upgrade a 100a service to 200a on a viewer's home. The segment was well done and thorough. He even used duct seal on the screws on the new box and in the penetration to the house siding and in the service mast pipe. I've never seen any electrician I've hired do that.
Standard SOP to prevent water intrusion and to seal from the elements of weather.

He made a point to note that the neutral and grounds must be bonded inside the service main, and the bonding screw tied the neutral bar to the panel case.
This part is to provide the bonding of the branch circuit grounded conductors and branch circuit neutrals and feeder neutrals to the service grounded conductor to complete the system circuits to the transformer (source)

The equipment grounds of the branch circuits and feeders bond on the neutral bar with the service neutral to complete the effective ground fault path to the transformer so circuit breakers can open on a ground fault.

The bonding screw makes sure any ground fault to the enclosure metal is part of the effective ground fault path back to the source.


He drove two rods under the meter socket at 6' apart and wired them together with a #6 copper wire which was set under a lug adjacent the neutral wire in the meter socket.
The water pipe bond requires a supplemental electrode .. in your case they chose a ground rod, since they did not test for ground resistance of 25 ohms or less they must drive two 8 foot long rods at least 6' apart.

The water pipe bond serves to bond the metal water piping system to the effective ground fault path in the event the pipes become energized. It also is required if the water pipe meets the definition of an existing grounding electrode and therefore must be used. The water pipe must be in contact with the earth for at least 10 feet to meet that definition.



The meter socket was outside, and the service panel was inside the basement about 2' away. What puzzled me was that he took another ground wire from the neutral buss bar and bonded to the water line. It was copper. Why didn't he just go the 2' back out the wall and bond it to the ground rod?
He could have but it causes some changes in design and grounding electrode conductor sizing to the ground rod. In the type installation the show was using with an interior panel as the service equipment it is much easier to land the bond on the neutral bar of the main panel.

I live in Texas. We don't have basements, and our water lines are plastic lines throughout my house, out to the water meter, and all the way back to the water supply facility. I've never seen a ground wire bonded to a water line around here. It just isn't done. I have seen grounds tied to gas pipes, however:eek:
The NEC lists acceptable grounding electrodes. Gas lines are not acceptable. If any of those listed are present you must use them and they must be bonded together. If none are present then you must install an acceptable grounding electrode system using electrodes from that list.



Could he have run that second ground wire back outside to the ground rod instead?
Yes
 
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Electrical only? Or other? I don't watch either enough to know...but what I have seen tells me that TOH certainly is way under target on electrical content, and Holmes thinks a common maple tree will electrocute you, unless he planted it.
A lot of stuff they have done, has been caught in certain points by people as unsafe. Pretty much every diy type show out there, you can catch a unsafe practice happen during the taping, that did not get edited out.
 

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\He drove two rods under the meter socket at 6' apart and wired them together with a #6 copper wire which was set under a lug adjacent the neutral wire in the meter socket.
I thought 200A needs #4 copper wire for ground.
 

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Not for ground rods, the GEC only needs to be a minimum of #6 copper. Water pipe bond would need to be #4 copper.
 

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This is the same show that showed a "professional licensed" electrician unhooking a drop that they stated was live, on one show segment.
Total disconnection would be odd but it depends. It is not unusual for the utility or the electrician that has been certified/permitted by the poco to repair splices at the drip loop live. It used to be very common until OSHA became more regulatory. You would be exposing yourself to huge liability by televising an unsafe disconnection of the utility.
Pulling the drop out fuse at the transformer is also common but they may not and probably will not if it will disconnect power to other residences ... which could cause some serious issues if people that are on oxygen machines or other medical equipment lose power not too mention heating in the winter. It is not always possible or cost effective to isolate a residence.
 

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Discussion Starter #13
Thanks Stubbie,

So if the metal water pipe system does not qualify as part of the GEC (10' minimum length of burial rule) then the required bonding jumper for a service main panel with a 200a disconnect would be #4 according to NEC 250.66. because the largest ungrounded service conductor in the panel would show to be 3/0 to supply the 200a breaker according to 310.15(B)(16) using 75 degree C wire.:thumbsup:

David
 

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This is the same show that showed a "professional licensed" electrician unhooking a drop that they stated was live, on one show segment.
This is not all that unusual. A lot of places, the POCO will not do it and actually will provide their seals and connectors to electricians. Yes it is dangerous and yes it could be in violation of OSHA practices if the proper paperwork, training, and PPE is not used. That doesn't mean it isn't commonplace. They made it adequately clear IMO on both episodes that the disconnect and reconnect should only be done by qualified people.

As for the show talked about by the OP, while correct and to code, the method was pretty hacky IMO. He used conduit for the riser, but SE for after the meter when conduit would have been better for sealing purposes. The three inch hole he cut through the wall and ledge joist was ridiculous in size to pass the cable through. Then he relies solely on a half ring of duct seal to weatherproof his ridiculous hole. He could have at least caulked the top of the meter pan. Also, if you've ever seen duct seal that's been exposed to the elements for a while, it becomes brittle and flaky.
 

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You bond panel to the cold water, so that if the copper does get energized, it will go back to earth ground. Inside breaker panel is bonded to meter pan through the Neutral, but meter pan is grounded by the ground wire to ground rod.. All of this is in the NEC, and what I just stated is the short version. BTW, stop watching Ask this old house. Worst than the crap that DIY shows on their regular shows.
Heres the only home improvement show worth watching in my book! :laughing:
 

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The NEC lists acceptable grounding electrodes. Gas lines are not acceptable. If any of those listed are present you must use them and they must be bonded together. If none are present then you must install an acceptable grounding electrode system using electrodes from that list.

Yes
I've never done one, but MA requires the gas line to be grounded if that yellow flex tube stuff (forget it's real name) is used. There was a big thing in 2009 about it, and lightening potential. Supposedly, a plumber is must hire an electrician to ground the gas pipe. (Although I'm guessing that never happens).

Last new construction I did, was required to tie all the rebar together in the foundation, footings, and bond it to the panel as well by the local AHJ, even with the two 10 foot rods.


-- Joe
 

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I've never done one, but MA requires the gas line to be grounded if that yellow flex tube stuff (forget it's real name) is used. There was a big thing in 2009 about it, and lightening potential. Supposedly, a plumber is must hire an electrician to ground the gas pipe. (Although I'm guessing that never happens).

Last new construction I did, was required to tie all the rebar together in the foundation, footings, and bond it to the panel as well by the local AHJ, even with the two 10 foot rods.


-- Joe
That would be bonding the gas line, not grounding.

The flex gas line is called CSST.
 

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That would be bonding the gas line, not grounding.
True. It is bonding not grounding. My mistake.

Here is a quote from Mike Holt, so apparently I'm not the only idiot that uses the terms incorrectly at times:

"Currently the NEC in Article 100 defines the terms "ground" or "grounded" as "connected to the earth or to some conducting body that serves in place of the earth." Yet, the NEC often uses the term "ground" when it really means "bond" (connected to an effective ground-fault path to clear a fault) [250.2 and 250.4(A)(5)]. "


-- Joe
 
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