Test question

[burner10501]

I recently took an Experior test, I didn't pass it, but how are you supposed to answer a question, that has "Maximum" size to a wire for ground or neutral, when everything I've been told about the code book is everything is based on the "Minimum" suggested size wire. I've never seen that question "Maximum" in any study material, and they had it in bold letters as well. Can you help me to decide which way to go on the answer, I know it sounds like a dumb question, but its not when your taking a test. Thank You

 

[ryan_618]

Re: Test question

The only thing I can of is that the maximum required grounding electrode conductor is 3/0, according to 250.66.

 

[roger]

Re: Test question

This is not helping but, out of curriosity, was the word "required" included in the question?

Roger

 

[roger]

Re: Test question

Ryan, I was thinking on the same line.

Roger

 

[ryan_618]

Re: Test question

It sounds like I'm in good company than

 

[burner10501]

Re: Test question

i don't remember the word required in the question, its the confusion of picking the right size wire for the application when they ask MAXIMUM, which when figuring any of these questions out in the field, which one to chose from the minimum or maximum, when all of the information in the code is figured on the minimum requirement, you have a 50 /50 chance. and I don't think that is what the code is all about. In the test there were not just one question like this, there was 4-5 like it in different applications

 

[charlie b]

Re: Test question

Originally posted by burner10501: I know it sounds like a dumb question, but its not when your taking a test.

No it?s not. The only dumb question is the one that appeared on the Experior test, and the dumbness was supplied by the author of the question.

In a word search of the 2002 code, I found 171 hits on the word ?maximum.? One context is the maximum rating of overcurrent protective device. Another is a maximum number of conductors (of a given size) that can fit into a given size and type of conduit. Another is the maximum load permitted on a branch circuit. But I do not know of a maximum size of conductor, in the context of our not being allowed to install a conductor larger than that size. So the only reasonable context is the one Ryan gave: the maximum size conductor that a code official can require us to install.

 

[burner10501]

Re: Test question

Thank You to all that responded to my question

 

[peter]

Re: Test question

Burner,
The experts have spoken. Experior has, I beleve, a mechanism for challenging a question. Perhaps you should pursue this.
~Peter

 

[rannon]

Re: Test question

For a grounding electrode conductors it is 12.5% of the largest ungrounded conductor, after the 1100 kcmil ceiling is met. Or, 12.5% of the total kcmil of paralleled ungrounded conductors.

For neutral conductors, the exact "K" of a common neutral can be derated for all ungrounded conductors on that multiwire branch ciruit under special conditions. Those being multiwire branch circuit conductors feeding HID lighting, dtatprocessing equipment, dimming ciruits, and any other application where harmonics are present.


For equipment grounding conductors, they don't have to be larger than the largest ungrounded conductor, taking into consideration voltage drop if needed.