Conduit Fill

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Conduit Fill (2)

Conduit Fill (2)

I appreciate your comments regarding this subject. I also applaud you for the direct response to (changing Breakers after Inspection). You are right. And I should not have asked the question to begin with.
After further study, I have found that I can get the #3s and the #8 in the 1" conduit after all. I also should have said THWN not THHN for underground burial. I have a feeling I will learn much from you folks, and I am very happy to have found all of you.......Thanks John Valdes
 
John Valdes said:
ibew441dc,
I worked out of local 349 Miami Fl. in the early 80's. Nice to meet you. Are you sure about your statement. I have only a 1" PVC conduit.
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John Valdes,
Nice to meet you too. I was about 2 years old in 1980.

As for my statement I am 100% positve as far as conductor fill is concerned.

I did my calculation assuming 1'' schedule 40 PVC was your raceway method and your wire isulation was thhn .

(note; all thhn I have ever seen, heard about, or installed had multiple ratings, such as thhn/thwn/mtw,etc).

Very little has changed in regards to the number and size of conductors in a raceway from 1996 to 2005 NEC cycle. 300.17 is the general rule to follow, it is supported by a FPN directing you to the appropriate raceway method.

Long story short, go to Table 1 in Chapter 9 in whatever code book you have and just follow the directions.

Hope this helped , I am realitively new to the forum and I think it is a great thing. I love the fact that many of us come from different backgrounds and experience.
As you already know you have to be careful about posting questions about cutting corners, you'll get a lot of heat on the forum. :mad: :grin:

take care ,

ibew441dc
 
Your right about the cutting corners question. I looked again at my 1996 code book and found that you can pull 4 #3s in the schedule 40 PVC. This leads me to believe that I am okay. Your response on the post was the most helpful. You used the formula. You didn't just jump all over me. What local are you a member of? I enjoyed many years with a great bunch of guys. Now that I am not working anymore it was nice to meet another brother IBEW guy,
 
Try a reduced neutral

Try a reduced neutral

Have you considered using a reduced neutral on that? For a 100 Amp sub-feed, we routinely install (2)#3's, (1)#4 neutral, and (1)#8 for your equipment ground. If you have any 240 Volt loads figured in there, you should be able to do this.

According to my calculations, they will fit (albeit a bit tight) into a 1" PVC and be Code compliant. ;)
 
John Valdes,

I am a member of Local 441 , Orange County , CA.

Electrical work is more than just another job to me, and what better an organization than the IBEW.

I am glad I could help. I'm sure you'll have an answer for me one of these days.:smile:

One thing that is for sure is that you have to give, in order to receive.
(espesially in our trade, nobody knows it all)

ibew441dc
 
One thing that is for sure is that you have to give, in order to receive.

One thing that is for sure is that you have to give, in order to receive.

ibew...you are correct. We will learn something everyday if we want to. Thanks for your help...John
 
I don't think anyone has asked this question yet, but do you really need 100 amps for this panel? 100 amps is more than sufficient for most small homes.

Have you done any type of load calculation or are you just winging it? You may be able to get away with something smaller, but you haven't specified what you are supplying. You said "cabana" so I am guessing this is for pool equipment.
 
John Valdes said:
rcarroll,
Thats what I thought. The inspector has already told me that he wants to see a four wire feeder. His point was that if I used a three wire feeder then I would be required to drive a ground rod. Since the out building is close to the lake his concern is that the resistance to ground would be less than the resistance at the main panel.......Thanks John
ps....the 90 amp breaker is a very good suggestion.
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You will need a ground rod (2 actually) if there is no other grounding electrode at the cabana. I'm assuming the cabana is a separate structure not attached to the house.
 
but do you really need 100 amps for this panel?

but do you really need 100 amps for this panel?

peter d said:
I don't think anyone has asked this question yet, but do you really need 100 amps for this panel? 100 amps is more than sufficient for most small homes.

Have you done any type of load calculation or are you just winging it? You may be able to get away with something smaller, but you haven't specified what you are supplying. You said "cabana" so I am guessing this is for pool equipment.
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Peter D,
When my sister started adding more loads everytime we talked I am not even sure the 100 amp service will be enough for the future. Her original plans were very modest. Now she will need a sewage lift pump & grinder, HW heater, indoor and outdoor lighting, Two boat lifts, large spa ect, small fridge, ice maker and more......
 
John, The inspector has told me not to drive a ground rod period. His concern is that the structure is so close to the lake that the ground potential will be greater at the structure than the main service. He insists that I use the existing ground and pull that conductor to the cabanna....feedback welcome

Note: The inspector has already approved going into the cabanna with an LB directly into the back of the distribution panel
 
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John Valdes said:
John, The inspector has told me not to drive a ground rod period. His concern is that the structure is so close to the lake that the ground potential will be greater at the structure than the main service. He insists that I use the existing ground and pull that conductor to the cabanna....feedback welcome

Note: The inspector has already approved going into the cabanna with an LB directly into the back of the distribution panel
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As I understand code the ground rod is not optional... only the ECG is optional. Since it is so close to the lake the inspector will probably only require one ground rod. Also don't forget the code now requires service disconnect at the remote structure (if more than 6 handles in the panel a main breaker qualifies) :wink:
 
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I agree with Dave, the Grounding Electrode is not optional, it is mandatory.

Roger
 
Hey guys, I also expected to drive one and maybe two ground rods. But as you all well know. "the inspector does not have to be right, you just have to do what he say's" And what he say's is going to save me alot of extra work. I learned a long time ago. Do not argue with the inspector, regardless of his/her lack of NEC knowledge.
Plus, I have to agree with him regarding the structure will have the least path of resistance to ground. Thus compromizing the main service ground...Feedback!
 
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John, why would you want to have a non compliant installation because some uninformed inspector says it is alright? That is simply a lame argument at best. Do it right regardless of what this person says. :roll: :roll: :roll:

Roger
 
John Valdes said:
I have to agree with him regarding the structure will have the least path of resistance to ground. Thus compromizing the main service ground...Feedback!
Click to expand...

John, I've been trying to figure these two sentences out but I think I should go ahead and ask, what do you mean by that, and what do you think a earthed connection does?

Roger
 
John,

Roger is 100% correct, check out 250.50 NEC 2005 for confirmation, also if

the water pipe to the cabanna is metal, and if a concrete footing with rebar

is installed they all have to tie together to form the GES. Your Inspector

should know this, and require it. Maybe it should be discussed agian??

Good luck,
 
Roger, Okay. The structure has a better ground than the main service. Example: you short circiut the range in the main service (the house). What breaker will trip? It will be a 50/50 chance it would be at the structure. Probably the main at the structure. In no circumstance do you want the least path of resistance to ground at the sub panel.
I have an email from the inspector, it goes as follows "Run your ground back to the house service. By no means should you ground close to the edge or lake"

Oh your second question....what do you think a earthed connection does?
Simply to allow the flow of wayward electrons a safe place to go....lol
 
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