Colorado JW Renewal Question

[George Stolz]

I just tried to renew my license, with my luck, the state website crashed before I hit the "submit" button. :roll:

Anyway, there was a question that drew my interest:

The minimum size copper grounding electrode conductor required to a concrete-encased electrode is:

A.) 8 AWG
B.) 6 AWG
C.) 4 AWG
D.) 2 AWG

What say you - or better still, what answer do you think they're expecting to hear?

 

[ryan_618]

8 AWG.

Typing here because my reply was too short

 

[stickboy1375]

C - #4 Awg

 

[ryan_618]

What were your thoughts George?

 

[George Stolz]

C - #4 Awg

My thoughts are, I wonder if the writer of the test would concur with Stickboy's answer.

 

[stickboy1375]

I went with #4 because it does not have to be bigger than that... if the sole connection... so even if I'm wrong on the test I'm code compliant. :grin:

 

[George Stolz]

That's a maximum, not a minimum. This is the sort of question that makes me start second-guessing what they intended to ask.

I hate stupid test questions being tricky for tricky's sake.

 

[ryan_618]

My thoughts are, I wonder if the writer of the test would concur with Stickboy's answer.

Even though its wrong?

 

[stickboy1375]

I would have to say the answer is #8 cu, since you have to use table 250.66
Thats the smallest size copper wire they have listed, but obviously I got that wrong since I read 250.66 (B) first...:grin: :grin: :grin:

 

[ryan_618]

That's a maximum, not a minimum. This is the sort of question that makes me start second-guessing what they intended to ask.

I hate stupid test questions being tricky for tricky's sake.

I've been asked by the International Code Council to serve on their Electrical Exam Development comittee. I'll be sure to add questions like this, just for you George.

I'll tell you what I do on questions like this...I challenge them...all of them, before I even know my test score. I write down why the answer is 8 AWG, just in case the question is worded wrong, or in case the person who wrote the question made a mistake. I remember challenging a few of the questions when I did my electrical plans examiner test, but the challenges didn't get reviewed because I passed the first time

 

[George Stolz]

My thoughts are, I wonder if the writer of the test would concur with Stickboy's answer.

Even though its wrong?

What if they intended to write "maximum"? That's really the only special relationship between a CEE and a GEC size in my book. :smile:

 

[JohnJ0906]

My teachers in apprentice school would mark "#8" as incorrect. You were supposed to write, "#8 in armor" (250.64(B)):roll:

 

[stickboy1375]

My teachers in apprentice school would mark "#8" as incorrect. You were supposed to write, "#8 in armor" (250.64(B)):roll:

Grounding conductors smaller than 6 AWG shall be in RMC, IMC, rigid nometallic conduit, EMT, or cable armor.

why would you say just "in armor"?

 

[Jljohnson]

I looked at that question a little bit differently George. 250.52(A)3 says that the CEE can be MADE from bare copper. Miminum of 20' long and # 4 Bare.
I answered "C".

 

[FrancisDoody]

I don't see any ambiquity in the question. NEC 250.52 A (3) is very clear that if you elect to use a bare copper conductor as your electrode it has to be no smaller than a #4. So I agree with Stickboy and everyone else who selected "C" as thier answer.
Thanks,
Fran

 

[ryan_618]

250.52(A)(3) describes the electrode itself, not the grounding electrode conductor. 8 AWG is permitted if the CEE is the rebar type.

 

[FrancisDoody]

I see what you mean that if you had selected rebar as your electrode that # 8 could be used. Interesting point. Thanks Ryan

 

[rcarroll]

I agree with Ryan. The question was for conductor size. P.S. George, I just submitted the master test renewal & passed.

 

[stickboy1375]

Would you rather be wrong on a test or correct in the field? :smile:

 

[JohnJ0906]

Grounding conductors smaller than 6 AWG shall be in RMC, IMC, rigid nometallic conduit, EMT, or cable armor.

why would you say just "in armor"?

Because that was the answer they required! IMO, it was a reminder to us that it had to be protected.