Burying a water bond

[kwired]

The first 5' inside isn't part of the electrode either, but 250.68(C) permits us to connect a GEC or bonding jumpers there.



Exactly... freezing would prevent that kind of water pipe installation in Ohio. The homeowner would have to use heat tape in the winter. A common scenario for mobile homes here... but the application of GES requirements don't present this problem for mobile homes because of the "remote" disconnect requirement.

Not that it is impossible, but I don't think I have ever seen metallic supply to mobile homes, and certainly haven't seen metallic water piping at all in any mobile home manufactured in past 20-25 years

 

[Smart $]

There are no requirements as to where the connections must be made other than accessable and it has a coviate that if it is barried it is not required provided the connector is listed for direct barrial.It can be at grade or bellow grade, if above grade it must be protected. 250.104 (A) (1) allows for bonding of water pipes atached to buildings. The phisical atribute of the copper water line does not change as it exits the ground and enters the structure.

What about 250.64(F)...

(F) Installation to Electrode(s). Grounding electrode con-
ductor(s) and bonding jumpers interconnecting grounding
electrodes shall be installed in accordance with (1), (2), or
(3). The grounding electrode conductor shall be sized for
the largest grounding electrode conductor required among
all the electrodes connected to it.
(1) The grounding electrode conductor shall be permitted
to be run to any convenient grounding electrode available
in the grounding electrode system where the other
electrode(s), if any, is connected by bonding jumpers
that are installed in accordance with 250.53(C).
(2) Grounding electrode conductor(s) shall be permitted to be
run to one or more grounding electrode(s) individually.
(3) Bonding jumper(s) from grounding electrode(s) shall
be permitted to be connected to an aluminum or copper
busbar not less than 6 mm ? 50 mm (1⁄4 in. ? 2 in.). The
busbar shall be securely fastened and shall be installed
in an accessible location. Connections shall be made by
a listed connector or by the exothermic welding process.
The grounding electrode conductor shall be permitted to
be run to the busbar. Where aluminum busbars are used,
the installation shall comply with 250.64(A).

I don't see where this permits connection of a GEC to an "electrical extension" of the electrode.

 

[Smart $]

Not that it is impossible, but I don't think I have ever seen metallic supply to mobile homes, and certainly haven't seen metallic water piping at all in any mobile home manufactured in past 20-25 years

Perhaps so... I haven't been involved with any mobile home water supplies in probably that long (or longer), but recall several back then that were supplied with soft copper lines.

 

[Smart $]

.... 250.104 (A) (1) allows for bonding of water pipes atached to buildings. ...

Bonding is an entirely different matter, except for when a GEC connection or an electrically continuous connection thereupon is coincidental and covers the bonding requirement... but the converse is not true.

 

[Gregg Harris]

What about 250.64(F)...



I don't see where this permits connection of a GEC to an "electrical extension" of the electrode.

And there is nothing that states that it can not be. In each subsection of 250 except for the type of connection and being accessable everything listed is permissive

 

[Gregg Harris]

Bonding is an entirely different matter, except for when a GEC connection or an electrically continuous connection thereupon is coincidental and covers the bonding requirement... but the converse is not true.

Technically it is all bonding. This example was given to show that the connection can be bellow grade,at grade, in the building and on the building

 

[Smart $]

And there is nothing that states that it can not be. In each subsection of 250 except for the type of connection and being accessable everything listed is permissive

I agree... all permissive... and that suggests (or infers, if you prefer) something is required or not allowed. 250.68(C) infers, outside exceptions, no GEC connection to a metallic water pipe can take place other than the electrode itself or interior metallic water pipe within the first 5' from entrance.

Technically it is all bonding. This example was given to show that the connection can be bellow grade,at grade, in the building and on the building

Perhaps interconnection, but no, it is not all technically bonding. Show me with Code where metallic pipe is a permitted bonding jumper. If it is all bonding, why is one conductor called a bonding jumper while another is called a GEC?

 

[kwired]

Show me with Code where metallic pipe is a permitted bonding jumper.

kind of getting back to your claim the first 5 feet of water pipe inside a structure is not an electrode here, but your question here complicates that a little depending on how you see those first 5 feet of pipe.

How about running a GEC to the first 5 feet from entry of the water pipe, then attaching a bonding jumper anywhere in those first 5 feet to continue on to another electrode?

The GEC must be continuous from attachment to service equipment to the electrode it supplies, first five feet of a water pipe is considered part of the electrode for the purpose of attachment of GEC or other bonding jumpers to or from this electrode.
s
Here is 250.52(A)(1) 2011 NEC:

(1) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth for 3.0 m (10 ft) or more (including any metal well casing bonded to the pipe) and electrically continuous (or made electrically continuous by bonding around insulating joints or insulating pipe) to the points of connection of the grounding electrode conductor and the bonding conductor(s) or jumper(s), if installed

Sure looks to me they intend to include the first 5 feet to be considered as part of the electrode for the purpose of attaching the GEC and jumpers to the electrode, I do understand those first 5 feet are not buried in earth and are not an effective part of performing the duties of the electrode.

Similar with a ground rod or other made electrode - the buried portion of the electrode must meet minimum length requirements to be considered an effective electrode, does the GEC connection to said electrode also need to be buried as long as there is enough buried section to the electrode? You can also attach a bonding jumper to this same exposed section of the electrode to run to other electrodes.

 

[jumper]

kwired, the first 5' of the water pipe is not an electrode, it is merely acceptable as an attachment point leading/close to the electrode.

CMP statements are pretty clear that this is their interpretation/intent. Can look up if necessary.

 

[kwired]

kwired, the first 5' of the water pipe is not an electrode, it is merely acceptable as an attachment point leading/close to the electrode.

CMP statements are pretty clear that this is their interpretation/intent. Can look up if necessary.

I agree it is not the electrode itself, it is permitted to be part of a bonding jumper, and if not part of the electrode then it must be a bonding jumper to the electrode if the GEC is attached to it.

 

[jumper]

I agree it is not the electrode itself, it is permitted to be part of a bonding jumper, and if not part of the electrode then it must be a bonding jumper to the electrode if the GEC is attached to it.

In truth, I am not sure what to call that 5' of pipe. :?

 

[GoldDigger]

What about 250.64(F)...



I don't see where this permits connection of a GEC to an "electrical extension" of the electrode.

No, but that electrical extension, not just the portion of the pipe which is below ground IS part of the electrode.

2011:

250.52 Grounding Electrodes.
(A) Electrodes Permitted for Grounding.
(1) Metal Underground Water Pipe. A metal underground water pipe in direct contact with the earth for 3.0 m (10 ft) or more (including any metal well casing bonded to the pipe) and electrically continuous (or made electrically continuous by bonding around insulating joints or insulating pipe) to the points of connection of the grounding electrode conductor ...

I don't see it being any simpler than that. There are separate restrictions as to where the connection can be made inside the building, etc., but the above ground pipe and extensions of it to wherever the GEC is (legally) attached are part of the permitted electrode.

 

[Smart $]

kind of getting back to your claim the first 5 feet of water pipe inside a structure is not an electrode here, but your question here complicates that a little depending on how you see those first 5 feet of pipe.

How about running a GEC to the first 5 feet from entry of the water pipe, then attaching a bonding jumper anywhere in those first 5 feet to continue on to another electrode?

The GEC must be continuous from attachment to service equipment to the electrode it supplies, first five feet of a water pipe is considered part of the electrode for the purpose of attachment of GEC or other bonding jumpers to or from this electrode.
s
Here is 250.52(A)(1) 2011 NEC:



Sure looks to me they intend to include the first 5 feet to be considered as part of the electrode for the purpose of attaching the GEC and jumpers to the electrode, I do understand those first 5 feet are not buried in earth and are not an effective part of performing the duties of the electrode.

Similar with a ground rod or other made electrode - the buried portion of the electrode must meet minimum length requirements to be considered an effective electrode, does the GEC connection to said electrode also need to be buried as long as there is enough buried section to the electrode? You can also attach a bonding jumper to this same exposed section of the electrode to run to other electrodes.

kwired, the first 5' of the water pipe is not an electrode, it is merely acceptable as an attachment point leading/close to the electrode.

CMP statements are pretty clear that this is their interpretation/intent. Can look up if necessary.

I agree it is not the electrode itself, it is permitted to be part of a bonding jumper, and if not part of the electrode then it must be a bonding jumper to the electrode if the GEC is attached to it.

In truth, I am not sure what to call that 5' of pipe. :?

You call it the first 5' of interior metal water pipe (from a metal water pipe electrode)

Greg Harris brought it up that the rules are all permissive... so anywhere the rule states "shall be permitted" it is an "option or alternative method", but not generally permitted. Yes the first 5' of interior water pipe serves as a GES conductor and also a GEC or bonding jumper terminal... but more specifically it is not textually called a bonding jumper.

 

[kwired]

Interesting points have been brought up. I can not say I totally agree or totally disagree with any of them. All I can say is I need to think similar to AHJ to have an easy time with inspections. When it comes to water piping and grounding electrodes, installations are typically similar from one place to another around here, easpecialy the fact that the piping will enter a structure at the lowest level and will enter from below grade, and not enter from above grade like in the OP of this thread.