310.15 C FPN 1

Status
Not open for further replies.

lavacano

Chadwick Ferguson, Safe and Sound Electric
Location
Washington State
Occupation
02 master
Section/Paragraph: 310.15 C FPN 1

Added Text

FPN No. 1: See ASHRAE Handbook—Fundamentals (???TABLE/CHAPTER???) (www.ashrae.org) as a source for the average ambient temperaturesin various locations.

REASON:

Don't reference stuff that doesn't exist. If it does exist, give lamen a fighting chance. See attached search for "average ambient temperatures" in the referenced handbook yielding no answers. If the ASHRAE doesn't give us what we need let us get our values from other data like an almanac.
 

Attachments

  • Capture.jpg
    Capture.jpg
    150 KB · Views: 0

luckylerado

Senior Member
Section/Paragraph: 310.15 C FPN 1

Added Text

FPN No. 1: See ASHRAE Handbook—Fundamentals (???TABLE/CHAPTER???) (www.ashrae.org) as a source for the average ambient temperaturesin various locations.

REASON:

Don't reference stuff that doesn't exist. If it does exist, give lamen a fighting chance. See attached search for "average ambient temperatures" in the referenced handbook yielding no answers. If the ASHRAE doesn't give us what we need let us get our values from other data like an almanac.

ASHRAE Design Temps do indeed exist and are relatively easy to find also local weather station data is allowed. ASHRAE is not the only source for this info.

Here is another source
 
Last edited:

lavacano

Chadwick Ferguson, Safe and Sound Electric
Location
Washington State
Occupation
02 master
ASHRAE Design Temps do indeed exist and are relatively easy to find also local weather station data is allowed. ASHRAE is not the only source for this info.

Here is another source

Then the NEC needs to define which value in that table "we all" will use. I see a lot of options and no formulas for finding a dead simple value. Seems like a huge cop out to me.
 

rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
This is a good example of applying the last sentence of Section 90.1(A). Several jurisdictions, e.g., the City and County of Los Angeles, actually declare what their design average ambient temperature is and for several specific applications as well such as attics and direct exposure to sunlight. Basically it is an AHJ judgment or what a design professional can sell to the AHJ. I usually documented my basis on any calculations that I submitted. In over 45 years, I rarely had to substantiate beyond the documented basis.

That said, there's nothing particularly wrong with your Public Input.
 

kwired

Electron manager
Location
NE Nebraska
Also keep in mind the FPN's, now called Informational notes, are just commentary/suggestions and not enforceable code content.
 
Status
Not open for further replies.
Top