Explain bonding jumper

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dereckbc

dereckbc

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Mr B-Inspector,

It is a length of a appropriately sized conductor to carry the intended fault current imposed upon it under the appropriate code section to clear a fault in a short amount of time. Sorry but your question is very vague like my answer. Read the definition in Article 100. Then come back and rephrase your question with a context to how it is used.

Example would be the EBC (aka EGC) ran with a 20 amp branch circuit. Minimum size would be from Table 250.122 a # 12 AWG copper or # 10 AWG aluminum conductor

Bonding Jumper. A reliable conductor to ensure the required electrical conductivity between metal parts required to be electrically connected.
 
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GoldDigger

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ActionDave said:
No kidding. A group of, well intentioned I'm sure, code making people managed to take an essential and simple concept and make it harder to learn or teach by giving us this alphabet soup of names for creating a fault current path.
Click to expand...
And all fault currents are required to work their way through the alphabet soup to decide which path(s) to follow. Fortunately that investigation occurs at roughly the speed of light. :)
 
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GoldDigger

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ActionDave said:
How easy is that to get lost by missing your exit? I have done it so many times and my top speed is 83MPH, going downhill.
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That is exactly the issue! :thumbsup: The electrons only figure out which way to go by literally taking all of the wrong paths.
Some of the electrons will initially miss their turns (taking alternate paths based on the transmission line characteristic impedances rather than the actual circuit termination impedances). They will not know they have missed their exit until the current reaches the dead ends at the other end of the wrong turns. They then turn around and go back to add their current to the flow down the correct paths.
The propagation of the current and voltage down the wrong paths and back again will be happening at about 60% of the speed of light.
But the first time the stray electrons get back to the intersection, some of them will blithely take other wrong paths until it eventually all sorts itself out.

If the voltage and current rise times are so high that this time scale is actually important, you get weird effects like lightning taking improbable paths. When it gets to the dead ends, it sometimes just keeps going. :)
 
ActionDave

ActionDave

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GoldDigger said:
That is exactly the issue! :thumbsup: The electrons only figure out which way to go by literally taking all of the wrong paths.
Some of the electrons will initially miss their turns (taking alternate paths based on the transmission line characteristic impedances rather than the actual circuit termination impedances). They will not know they have missed their exit until the current reaches the dead ends at the other end of the wrong turns. They then turn around and go back to add their current to the flow down the correct paths.
The propagation of the current and voltage down the wrong paths and back again will be happening at about 60% of the speed of light.
But the first time the stray electrons get back to the intersection, some of them will blithely take other wrong paths until it eventually all sorts itself out.

If the voltage and current rise times are so high that this time scale is actually important, you get weird effects like lightning taking improbable paths. When it gets to the dead ends, it sometimes just keeps going. :)
Click to expand...
For their sake I pray and hope none of these electrons are in the same car with their wives while sorting this out.
 
jwelectric

jwelectric

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If I am installing a bonding jumper from the coping to the rebar in the concrete at a pool is this bonding jumper being installed to carry fault current? :?

I didn?t know that all bonding jumpers were installed to carry fault current! :jawdrop:
 
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shortcircuit2

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Types of Bonding Jumpers?

Types of Bonding Jumpers?

The NEC tells me types of bonding jumpers are...

1.Conductor (Implied by the NEC to be a Wire)

2.Bus

3.Screw

4.Similar Suitable Conductor (Anybody have an example of this?)

I understand that the definition of "conductor" relative to electrical work to generally be of the wire type.

Is this how others interpret the definition of a conductor?
 
K8MHZ

K8MHZ

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shortcircuit2 said:
The NEC tells me types of bonding jumpers are...

1.Conductor (Implied by the NEC to be a Wire)

2.Bus

3.Screw

4.Similar Suitable Conductor (Anybody have an example of this?)

I understand that the definition of "conductor" relative to electrical work to generally be of the wire type.

Is this how others interpret the definition of a conductor?
Click to expand...

I think #4 relates to the things that are made to connect a neutral bus bar to the panel it's mounted on. One end has a hole to put a screw through, the other is a rod about the size of a #8 wire, which goes into one of the terminals in the neutral bar. I don't know what they are called.
 
J

John120/240

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K8MHZ said:
I think #4 relates to the things that are made to connect a neutral bus bar to the panel it's mounted on. One end has a hole to put a screw through, the other is a rod about the size of a #8 wire, which goes into one of the terminals in the neutral bar. I don't know what they are called.
Click to expand...

#4
I use SQ D. They have two styles of lugs that you can use on a neutral bus. One is a straddle lug that fits over the neutral bus and straddles the bus. The other is a add-a-lug. A lug with two prongs that fit under your neutral bus screws, then your # 2 fits in the add-a-lug.
 
Little Bill

Little Bill

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K8MHZ said:
I think #4 relates to the things that are made to connect a neutral bus bar to the panel it's mounted on. One end has a hole to put a screw through, the other is a rod about the size of a #8 wire, which goes into one of the terminals in the neutral bar. I don't know what they are called.
Click to expand...

John120/240 said:
#4
I use SQ D. They have two styles of lugs that you can use on a neutral bus. One is a straddle lug that fits over the neutral bus and straddles the bus. The other is a add-a-lug. A lug with two prongs that fit under your neutral bus screws, then your # 2 fits in the add-a-lug.
Click to expand...

No, what K8MHZ is referring to is the bonding jumper, that among others, Eaton uses.
It is as he described, a short piece of metal that is rounded on the end about the size of #8 wire, then has an offset and then flattened on the end with a screw hole. It usually comes attached to the panel via the screw hole but is not connected to the neutral bus.

For a panel that is to be bonded you just swing it up to line up with a screw terminal in the neutral bar. You then place it in the terminal and tighten it down, also tighten the screw that attaches the jumper to the can. This makes the bond between the neutral and the metal of the cabinet and grounding bar.
 
J

John120/240

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Location
Olathe, Kansas
Little Bill said:
No, what K8MHZ is referring to is the bonding jumper, that among others, Eaton uses.
It is as he described, a short piece of metal that is rounded on the end about the size of #8 wire, then has an offset and then flattened on the end with a screw hole. It usually comes attached to the panel via the screw hole but is not connected to the neutral bus.

For a panel that is to be bonded you just swing it up to line up with a screw terminal in the neutral bar. You then place it in the terminal and tighten it down, also tighten the screw that attaches the jumper to the can. This makes the bond between the neutral and the metal of the cabinet and grounding bar.
Click to expand...

Thanks Bill, that explains it. Tub to neutral bus bond. Flatt on one end to attach to tub, round on other to attach to bus
 
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Nice Cat

Nice Cat

Thats a fine looking Tabby Cat.
 
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