250.102(E) out of pipe grounding

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dnem

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Code legal ?

Here's the scenerio:

Two panels side by side, less than 6 feet apart. . One panel feeds the other panel. . All circuit conductors are in a short conduit between the panels as per 300.3(B) except the equipment grounding conductor which is run outside of the conduit. . Altho 250.134(B) says that the "equipment grounding conductor" must be in the conduit, the contractor says that his conductor is an "equipment bonding jumper" and is allowed outside of the conduit by 250.102(E).

NEC Legal ?

Question 2:

2005 Handbook page 223 Exhibit 250.43
If I stick that green wire inside the flexible metal conduit, is it still a bonding jumper or is it an equipment grounding conductor ?

David
 
Is an EGC required?

What I mean is the conduit already a 250.118 EGC?

If the conduit is an EGC it seems the EC could voluntarily add the bonding jumper.
 
Also, 250.134(B) says "With Circuit Conductors. By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors."

So the question becomes, what does "otherwise run with the circuit conductors" mean? Is a wire on the outside of a conduit run with the others?

With the convoluted grounding, bonding, and jumper definitions, I don't know what this wire really is. I really need to get the handbook, so I can see those clarifying pictures.
 
suemarkp said:
With the convoluted grounding, bonding, and jumper definitions, I don't know what this wire really is. I really need to get the handbook, so I can see those clarifying pictures.
Click to expand...

That's what I'm thinking. . The more I try to put a precise dividing point between equipment grounding conductor and equipment bonding jumper, the further away I find myself.

The Article 100 definition for Bonding Jumper, Equipment says, "The connection between two or more portions of the equipment grounding conductor." . Then I look at the Handbook page 223 Exhibit 250.43 and it shows a picture that has a "bonding jumper" run outside of the conduit and not terminated at an equipment grounding conductor at either end. . At one end it's screwed to the panel housing, at the other end it's screwed to the motor housing.

Look at that picture and see if you can figure out the dividing line between an equipment grounding conductor and an equipment bonding jumper.

David
 
Well don't keep us in suspension !

Look up Handbook page 223 Exhibit 250.43 or 250.102(E) and tell us what Mike Holt says
 
Dnem,


"Alex, I'll take Mike Holt's Grounding vs Bonding for $178 please"!


/sarc>
 
dnem said:
250.102(E) "The equipment bonding jumper shall be permitted to be installed inside or outside of a raceway .....
Click to expand...

Exactly. Lets read [E} --->250.119/250.148.

Thus they are EGC's. Not jumpers.

WE are just parsing. But the OP cant be both.
 
Okay. Let's unravel step by step...


Def Grounding conductor,equipment The conductor used to connect the non-current carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor, the grounding electrode, or both, at the service equipment or at the source of a seperately derived system.

Def Bonding jumper, Equipment The connection between two or more portions of the equipment grounding conductor.

Now lets consider the purposes of a couple of concepts....

250.4 General Requirements for Grounding and Bonding

(A)Grounded systems
(1)Electrical System Grounding - Electrical systems that are grounded shall be connected to the earth in a manner that will limit the voltage imposed by lightning, line surges, or stabilze the voltage to earth during normal operation.



Rocky's comment -
Grounding is about connecting to the earth for lightning and high voltage induced, NOTHING to do with OCPD protection! That thought is fortified by the next section(s) in the code -

(2)Grounding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected to earth so as to limit the voltage to ground of these materials.

(3)Bonding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected together and to the electrical supply source in a manner that establishes an effective ground fault current path.



Rocky's comment -

So now we understand that grounding and bonding are for totally different reasons, let's reiterate. Grounding is to send lightning and line surges(high voltage) to earth. Bonding (via an effective ground-fault current path) is to facilitate operation of the OCPD!

So let's go back to the NEC Handbook and what it says on page 223 -

Code -
250.102(E) installation The equipment bonding jumper shall be permitted to be installed inside or outside of a raceway or enclosure. Where instaled outside, the length of the equipment bonding jumper shall not exceed 1.8m (6 ft) and shall be routed with the raceway or enclosure. Where installed inside of a raceway, the equipment bonding jumper shall comply with the requirements of 250.119 and 250.148.

Exception: An equipment bonding jumper longer than 1.8m in (6 ft) shall be permitted at outside pole locations for the purpose of bonding or grounding isolated sections of metal raceway or elbows installed in exposed risers of metal conduit or other raceway.

Handbook commentary -
In many applications, bonding jumpers must be installed on the outside of metal racewaysand enclosures. For example, it would be impractical to install the bonding jumper for a conduit expansion joint on the inside of the conduit. For some metal raceway and rigid conduit systems and conduit systems in hazardous (classified) locations, installing the bonding jumper where it is visible and accessible for inspection and maintenace is desireable. an external bonding jumper has a higher impedance than an internal bonding jumper, but by limiting the length of the bonding jumper to 6 ft and routing it with the raceway, the increase in the impedance of the equipment grounding circuit is insignificant. Exhibit 50.43 illistrates a bonding jumper run outside length of flexible metal conduit. Because the function of a bonding jumper is readily apparent, color idientification is permitted, but not required.

I can't get a picture here so visualize -

A GRC conduit entering a 60 A disco with a CB and heaters in it. A piece of 1" FMC exiting to a motor (less than 6') with a #10 (green insulation) ty-wrapped to it. The bonding jumper is attached using recognized, listed fittings for attachments on the disco, and the other end, on motor terminal housing.

Thsi is backed by the 250.118(6)




So to wrap up the OP's questions -

David,

1)Per NEC you can run it on the outside.

2)Per NEC The bonding jumper can be the equipment grounding conductor.

These are opinions only (but I think they're valid with the code sections sited). Check your local adendums as to where they stand with the code.
 
Last edited:
Alex,


"Grounding vs Bonding headache relief for a $1000"


"Hey, it's a daily double!"
 
Rocky,
Your post is technically correct but doesn?t take into consideration the reality of how the code is written. . For years now people have written code proposals to change the code term ?equipment grounding conductor? to ?equipment bonding conductor? and the code panel hasn?t been willing to act. . They have not acted because the term equipment grounding conductor is so entrenched in everyones mind.

Rockyd said:
(1)Electrical System Grounding - Electrical systems that are grounded shall be connected to the earth in a manner that will limit the voltage imposed by lightning, line surges, or stabilze the voltage to earth during normal operation.

Rocky's comment -
Grounding is about connecting to the earth for lightning and high voltage induced, NOTHING to do with OCPD protection! That thought is fortified by the next section(s) in the code -

(2)Grounding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected to earth so as to limit the voltage to ground of these materials.

(3)Bonding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected together and to the electrical supply source in a manner that establishes an effective ground fault current path.
Click to expand...


And the function of the effective ground fault current path is to operate the OCD.
And the function of the equipment grounding conductor is to provide a ground fault current path that operates the OCD. . It?s a conductor that is named ?grounding? but its function is ?bonding?.

Rockyd said:
David,

1)Per NEC you can run it on the outside.

2)Per NEC The bonding jumper can be the equipment grounding conductor.
Click to expand...

Saying that the bonding jumper can be the equipment grounding conductor is totally acceptable ?codespeak? but technically it is nonsense, as you proved by your post.

Rockyd said:
(2)Grounding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected to earth so as to limit the voltage to ground of these materials.

(3)Bonding of Electrical equipment Non-current carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be connected together and to the electrical supply source in a manner that establishes an effective ground fault current path.
Click to expand...


Because ?codespeak has so bastardized the word ?grounding? by muddling its usage in the code, I know of many people that don?t use the words ?bonding? and ?grounding? any longer when they want to talk about function. . They say ?bonding? and ?earthing?.
?Bonding? is effective ground fault current path to operate OCD.
?Earthing? is lightning [overvoltage] protection and reference to earth.
?Grounding? is a muddled NEC code word that has ceased being useful as a word that describes function. . It?s just a label for certain equipment or conductors.

My point that relates to this whole conversation is that the fact that the wire is called an equipment grounding conductor is meaningless. . It?s a label not a function. . And the word ?ground? is also used in the code in every conceivable way. . Ungrounded, grounded, equipment grounding [bonding], electrode grounding [earthing]. . In my opinion it?s overused ?.. or actually I should say that it?s too overly and loosely used as a label to still retain any usefulness as a word that describes function.

I don?t think focusing on that word is helpful in determining the correct answer to my original questions.

Where?s that guy with the Mike Holt book ?

David
 
300.3(B) Conductors of the Same Circuit. . All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4).

300.3(B)(2) Grounding and Bonding Conductors. . Equipment grounding conductors shall be permitted to be installed outside a raceway or cable assembly where in accordance with the provisions of 250.130(C) for certain existing installations or in accordance with 250.134(B), Exception No. 2, for dc circuits. . Equipment bonding conductors shall be permitted to be installed on the outside of raceways in accordance with 250.102(E).

250.130 ?.. For replacement of non-grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C). . [And (C) says to run the equipment grounding conductor to an grounding electrode conductor or to the service main for that specific limited situation only]

250.134(B) With Circuit Conductors. . By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors. . [I am under the impression that ?otherwise run? refers to 300.3(B) same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord]
Exception 1: nongrounding receptacle replacement
Exception 2: dc circuits

250.102(E) Equipment Bonding Jumpers. Installation. . The equipment bonding jumper shall be permitted to be installed inside or outside of a raceway or enclosure. . Where installed on the outside, the length of the equipment bonding jumper shall not exceed 1.8 m (6 ft) and shall be routed with the raceway or enclosure. . Where installed inside of a raceway, the equipment bonding jumper shall comply with the requirements of 250.119 and 250.148. . [250.119 is identification, 250.148 is connections]

My conclusions:
A) The last sentence of 300.3(B)(2) uses the term ? equipment bonding conductors? interchangeably with the term ?equipment bonding jumpers? in 250.102(E).

B) It?s interesting that 250.102(E) says the equipment bonding jumper shall comply with the requirements of 250.119 and 250.148. . And both of those references talk about the equipment grounding conductor.

C) It?s obvious that equipment bonding jumper and equipment grounding conductor are close to identical. . But 300.3(B)(2) definitely speaks of then in two separate sentences that have slightly different requirements.

There?s probably only a few possible differences. . I really didn?t want to suggest a definition. . I was hoping someone would step forward with a definite answer. . Since noone is interested in giving it a try, let me post the definition that I was told elsewhere and you tell me what you think:
DEFINITIONS
The equipment ground is a bonding jumper/conductor if:
it is outside of the raceway 6 ft or less and routed with raceway [250.102(E)] or non-electrode metal bonding [such as 250.104, 680.26(B), 680.43(D)],
or it is inside of a raceway that is 2 feet or shorter [Chapter 9 Notes to Tables(3)+(4)],
or both ends are terminated in the same enclosure [250.24(B), 250.30(A)(1)].

The equipment ground is a grounding conductor if:
it is outside of a raceway for nongrounding receptacle replacement or dc circuits [250.134(B)x1+2]
or it is inside of a raceway that is longer than 2 feet.

David
 
dnem said:
300.3(B) Conductors of the Same Circuit. . All conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord, unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4).

300.3(B)(2) Grounding and Bonding Conductors. . Equipment grounding conductors shall be permitted to be installed outside a raceway or cable assembly where in accordance with the provisions of 250.130(C) for certain existing installations or in accordance with 250.134(B), Exception No. 2, for dc circuits. . Equipment bonding conductors shall be permitted to be installed on the outside of raceways in accordance with 250.102(E).

250.130 ?.. For replacement of non-grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C). . [And (C) says to run the equipment grounding conductor to an grounding electrode conductor or to the service main for that specific limited situation only]

250.134(B) With Circuit Conductors. . By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors. . [I am under the impression that ?otherwise run? refers to 300.3(B) same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord]
Exception 1: nongrounding receptacle replacement
Exception 2: dc circuits

250.102(E) Equipment Bonding Jumpers. Installation. . The equipment bonding jumper shall be permitted to be installed inside or outside of a raceway or enclosure. . Where installed on the outside, the length of the equipment bonding jumper shall not exceed 1.8 m (6 ft) and shall be routed with the raceway or enclosure. . Where installed inside of a raceway, the equipment bonding jumper shall comply with the requirements of 250.119 and 250.148. . [250.119 is identification, 250.148 is connections]

My conclusions:
A) The last sentence of 300.3(B)(2) uses the term ? equipment bonding conductors? interchangeably with the term ?equipment bonding jumpers? in 250.102(E).

B) It?s interesting that 250.102(E) says the equipment bonding jumper shall comply with the requirements of 250.119 and 250.148. . And both of those references talk about the equipment grounding conductor.

C) It?s obvious that equipment bonding jumper and equipment grounding conductor are close to identical. . But 300.3(B)(2) definitely speaks of then in two separate sentences that have slightly different requirements.

There?s probably only a few possible differences. . I really didn?t want to suggest a definition. . I was hoping someone would step forward with a definite answer. . Since noone is interested in giving it a try, let me post the definition that I was told elsewhere and you tell me what you think:
DEFINITIONS
The equipment ground is a bonding jumper/conductor if:
it is outside of the raceway 6 ft or less and routed with raceway [250.102(E)] or non-electrode metal bonding [such as 250.104, 680.26(B), 680.43(D)],
or it is inside of a raceway that is 2 feet or shorter [Chapter 9 Notes to Tables(3)+(4)],
or both ends are terminated in the same enclosure [250.24(B), 250.30(A)(1)].

The equipment ground is a grounding conductor if:
it is outside of a raceway for nongrounding receptacle replacement or dc circuits [250.134(B)x1+2]
or it is inside of a raceway that is longer than 2 feet.

Gmack's IMO:

We cannot and should not tamper with the "fine line" as first described in the OP.

Why? Because if we do not keep them "blurred" together, we may open up a can that we do not want.

How? Because bonding will lose the ever needed "tie" to grounding all the way back to the main.

Consider that a electrician would only be concerned about bonding some "parts" and not be thinking of "ground".

Also IMO the NEC has to drive it again and again into everyones head that we ground the "grounded conductor" and it must be ever present that we "bond" the EGC's to it. At the main.

Going down a path of de linking for the sake of better english would be a mistake IMO.

2cents.
Click to expand...
 
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