Charts for AWG-CMA

[dffnc]

I'm looking for a chart (readable) on the internet that provides the CMA for the various sizes of wire. I need to do some calculations on voltage drop over a distance and can't find a chart that I can read. If all else fails I can get one from the NEC at a bookstore or maybe the library but was hoping to be able to download one.

If anyone knows a formula to determine the CMA as related to AWG that works too. I can calculate CMA needed based on other information but don't have any method to then transfer it to AWG.

Thanks.

[Wgoodrich]

Not aware of an electronic copy of the ampacity charts. Don't forget ampacity deration concerns of more than 3 current carrying conductors in a raceway and ambient temperature deration charts that also derate ampacity of conductors. You want a copy of Table 310.16 normally in your quest for ampacity of conductors.

You circular mill of a conductor area and the resistance of that conductor required to be used by the NEC can be found in table 8 of chapter 9 of hte NEC concerning your voltage drop calculations.

A couple of articles found in our homewiringandmore.com web site may be of help to you also, try the following two links

http://www.homewiringandmore.com/homewiringusa/2002/definitions/ampacity/amp.html

http://www.homewiringandmore.com/homewiringusa/2002/definitions/voltagedrop/voltagedrop.html

Sorry Couldn't help you a lot on this one.

Wg

[dffnc]

Thanks for trying. I'll go to the local library and borrow a copy of the NEC to get the charts.

Thank you too for reminding me to check the other tables. I've been reading the various articles and posts on the site. They have been very informative and helpful. I appreciate being able to use the site for the ideas and information.

[Wgoodrich]

You could go to the library or the Code Enforcement office and ask them to photo copy a certain table in the NEC as you need. Should be low in cost and fast retrieving what you are looking for. You probably could ask for TAble 310.15.B.6 and Table 310.15.B.2.A and Table 8 of Chapter 9. This would provide the charts you need to calculate ampacity of a conductor including derations and voltaged drop calculations as you desire.

Problem with us providing these charts on the net would be a violation of any copyright laws. It takes great effort to write what we have on this web site homewiringandmore.com to give to the world for free. We can't even imagine the effort of uncountable people involved in writing the NEC itself. The homewiringandmore.com is written as a two complete selfhelp books providing a community service. There may be and probably is misspelling, bad grammer, misunderstood reading in these two books that I have written and provided as a free community service to all mankind regardless of who that man kind is and what walk of life they live by. In doing these self help books it should be a given that I am providing masses of information but in a common language self help informative desire and manner to help other people trying to help themselves. Gives me some room to make a few [probably a lot] of mistakes along the way of writing these books found on our web site.

The NEC while not written as law is written with the intent to be adopted as law. One dot or comma out of place could cause massive legal battles over what is said. The NEC is written in a manner that unforgiving of mistakes. Maybe that is why it is so hard to understand and interpret. However with this technical accuracy demands on this written NEC book we must respect their copy right.

I do believe it is intended during the use and interpretation of the NEC that it is allowed that you copy a certain section for your utilization of that certain section of the NEC. The Code enforcement and or your library should have no problem providing the copied charts for you.

Let us know how you come out.

Good Luck

Wg

[dffnc]

I went to the local library and pulled the charts. I really only needed the information for a few sizes of wires, so was able to just take notes to get the specific information I wanted. I already had the formulae for voltage drop calculations and for CMA needed. So, I just plugged in the CMA for the various AWG sizes.

Thanks for the service you provide to all of us out here struggling to maintain our homes and outbuildings. I'm sure I speak for all of us who have sought your assistance when I say we appreciate it greatly.

[Wgoodrich]

Thank you for your voice of appreciation. All I ask is do unto others as others have done unto you. If you know something or can help someone even a perfect stranger then please do so. Take it as a payment to me for our time helping you. If we all did this then the world would be a lot better than it is now. It is a great world but we can make it better. YOu kind thoughts mean a lot to me.

Thanks again

Wg