Table 310.15(B)(16)

[ggunn]

What we have are requirement statements which are either implicit, inferred, or explicit. I do not see any of the last, perhaps at best bordering the middle, and a lot of the first. Your last sentence alone proves you have to make a leap of faith to implement.




For the most part, I agree with the notion we should use the highest temperature... but you can't average the high temperature for any one year period. It is either the high or it is not. Anything lower is whatever you want to call it, whether accurate, useful, or not.

All I'm saying is if the adders are based on "averaging the ambient temperatures", we have no true grounds to add them to the highest anticipated ambient temperature. To do so is an assumption not based on fact.

FWIW, what a lot of folks in PV use is the highest monthly average high from weather.com.

 

[Dennis Alwon]

For the most part, I agree with the notion we should use the highest temperature... but you can't average the high temperature for any one year period. It is either the high or it is not. Anything lower is whatever you want to call it, whether accurate, useful, or not.

If you mean the highest one day temperature then I think that is crazy. One day high temp. is not going to degrade the insulation on the conductor at all. In fact it wouldn't even be that high for 24 hours. This clearly needs explaining for us to understand what the cmp members are requiring, IMO.

All I'm saying is if the adders are based on "averaging the ambient temperatures", we have no true grounds to add them to the highest anticipated ambient temperature. To do so is an assumption not based on fact.

Agreed

 

[Smart $]

If you mean the highest one day temperature then I think that is crazy...

I do, too!... So for the record, I was only talking in the context of GoldDigger's post.

 

[James S.]

If you mean the highest one day temperature then I think that is crazy. One day high temp. is not going to degrade the insulation on the conductor at all. In fact it wouldn't even be that high for 24 hours. This clearly needs explaining for us to understand what the cmp members are requiring, IMO.

I had not really thought of this. That alone helps me a lot. I will read the links you gave earlier when I get a bit more time.

I have to say that I am feeling a bit vindicated just from the discussion you guys are having. It is obviously not so cut and dried as I might have thought it was.