grounding electrode conductor must be connected to

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race

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my exam question went like this........
The grounding electrode conductor must be connected to
the--------at the main distrubution panel.

a. at the ungrounded conductor
b. at the neutral terminal bus
c. at the equipment grounding terminal bus
d. at the grounding bushing
 
race said:
i would like to know the answer Bob they say b. is the answer
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Two things wrong with 'b' in my opinion.

1) The NEC does not call it a neutral terminal bus they call it the bus that the grounded conductor is connected to.

2) The GEC does not have to run into the service enclosure, it could run up the weather head on an overhead service.

I think the question is bad.
 
thank you for your time my next class is thursday so we will see if my grade will be changed from 93% to 100%...........thanks again
 
race said:
my exam question went like this........
The grounding electrode conductor must be connected to
the--------at the main distrubution panel.

a. at the ungrounded conductor
b. at the neutral terminal bus
c. at the equipment grounding terminal bus
d. at the grounding bushing
Click to expand...

In my opinion, it takes highly knowledgeable people to create an intelligent, fair test and whoever created this one didn't have so much as an inkling of electrical prowess.......and that's a damned shame when one considers the grading affixed to such a poor document. Good luck. Maybe there should be licensing and certification of exam preparers...:smile:
 
When questions are poorly written you have to choose the best answer. IMO given the choices b. is the best answer, although d. may also be correct if the GEC is installed in a ferrous raceway.
 
infinity said:
When questions are poorly written you have to choose the best answer. IMO given the choices b. is the best answer, although d. may also be correct if the GEC is installed in a ferrous raceway.
Click to expand...

(D) can be correct if the bonding jumper is a wire or bus.If a screw is used, it 's gotta go the grounded conductor terminal bar.
I agree (B) is the best answer.
Rick
 
race said:
my exam question went like this........
The grounding electrode conductor must be connected to
the--------at the main distrubution panel.

a. at the ungrounded conductor
b. at the neutral terminal bus
c. at the equipment grounding terminal bus
d. at the grounding bushing
Click to expand...

I would chose B because that is what the manufacture calls it and because the neutral and ground lugs are side by side normally..I know we will see several examples of them being seperated and feel free to show and the manufactures wording as well..this will give the young man/women the documentation to win their arguement..
 
The main distribution panel is not necassarily where the main breaker is located it could be fed with buss extension if you don't believe me
then ask ROGER. :D
 
RUWired said:
(D) can be correct if the bonding jumper is a wire or bus.If a screw is used, it 's gotta go the grounded conductor terminal bar.
I agree (B) is the best answer.
Rick
Click to expand...


I'm not sure I follow. If the GEC is in a ferrous raceway then it is required to be bonded to that raceway typically by using a grounding/bonding bushing as outlined in answer d.
 
infinity said:
I'm not sure I follow. If the GEC is in a ferrous raceway then it is required to be bonded to that raceway typically by using a grounding/bonding bushing as outlined in answer d.
Click to expand...

Yes it is required to be bonded but not allowed to terminate at that point.
 
I just installed a (200A) Main disconnect panel on a pole for a mobile home service.
It sits directly below the meter and is connected to the meter base by PVC conduit.
It's fed by 3 conductor (4/0 Al) USE cable from meter to disconnect.

The main disconnect (metal) enclosure has a aluminum terminal bar that has only 3 lugs, one for the service grounding conductor, one for the GEC, and one for the Grounded feeder conductor to the house.

This bar also has a #10 green (main) bonding screw to bond it and a additional (seperate) equipment grounding bar to the enclosure.
This equipment grounding bar is bolted to the enclosure.

I landed the GEC and the grounded (feeder) conductor on the terminal beside the grounded service conductor, installed the bonding screw, and landed the feeder grounding conductor (to the home) on the seperate (bonded) grounding bar.

I really don't like this set-up, although I believe that I installed it correctly.
I don't like it because the 2/0 Al (feeder) equipment grounding conductor depends on the green #10 bonding screw for it's connection to the service ground.

It seems to me that the GEC should be landed on the equipment ground bar, and the Feeder grounding conductor landed on the same ground bar as the service ground.
This would assure a better grounding connection for the feeder and not depend on the screw for bonding all of the house equipment grounds.


Maybe I'm wrong, but I'd rather have a better (lower impedance)connection for the (feeder) EGC than the Grounding electrode conductor.

This Main breaker panel is a new (for me) brand.

It seems like the NEC places a lot of faith in a #10 screw to provide a sufficient, long lasting bond between the grounded service conductor and the equipment ground.

I know that it's in the code, but it seems kind of weak to me.

Any comments, or suggestions?

steve

ps....I think that the (correct?) answer to the OP's question is "B".
 
wbalsam1 said:
In my opinion, it takes highly knowledgeable people to create an intelligent, fair test and whoever created this one didn't have so much as an inkling of electrical prowess.......and that's a damned shame when one considers the grading affixed to such a poor document. Good luck. Maybe there should be licensing and certification of exam preparers...:smile:
Click to expand...

I agree,

I teach electrical apprenticeship in my area and some of the test questions that I am asked to give the students are absolutely asinine. I also have some serious problems with some of the state license exam questions.

Chris
 
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