converting kcmil to cm sizing grounded conductor

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zcanyonboltz

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denver
How do you convert 1200 kcmil to mil. I'm multiplying 1200 by 10 to get 12,000 which multiplied by 12.5% gives me 150,000cm
I'm not sure what to multiply cm by to get kcmil or what to divide kcmil mil by to cm? Thanks

3 phase conductors of 400 kcmil conductors= 1200 kcmil x 12.5% =150,000cm
Chapter 9 table 8 150,000 cm = 3/0 THW Cu.
250.102 (C) (1)

1/0 = 105,600 cm x 2 = 211,200 cm would this be 211 kcmil?
 

kwired

Electron manager
Location
NE Nebraska
How do you convert 1200 kcmil to mil. I'm multiplying 1200 by 10 to get 12,000 which multiplied by 12.5% gives me 150,000cm
I'm not sure what to multiply cm by to get kcmil or what to divide kcmil mil by to cm? Thanks

3 phase conductors of 400 kcmil conductors= 1200 kcmil x 12.5% =150,000cm
Chapter 9 table 8 150,000 cm = 3/0 THW Cu.
250.102 (C) (1)

1/0 = 105,600 cm x 2 = 211,200 cm would this be 211 kcmil?

"k" means 1000.

1kcmil = 1000 circular mills.

yes 211,200 cm is 211.2 kcmil (didn't check for any accuracy as to how you came up with 211,200)
 

infinity

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New Jersey
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Journeyman Electrician
How do you convert 1200 kcmil to mil. I'm multiplying 1200 by 10 to get 12,000 which multiplied by 12.5% gives me 150,000cm
I'm not sure what to multiply cm by to get kcmil or what to divide kcmil mil by to cm? Thanks

3 phase conductors of 400 kcmil conductors= 1200 kcmil x 12.5% =150,000cm
Chapter 9 table 8 150,000 cm = 3/0 THW Cu.
250.102 (C) (1)

1/0 = 105,600 cm x 2 = 211,200 cm would this be 211 kcmil?

What is the bold part?
 

GoldDigger

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Location
Placerville, CA, USA
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Retired PV System Designer
There is a fundamental problem with this whole discussion: the circular mil is a unit of area, equal to .7854 square mils. The centimeter, cm, is a unit of length!
You could, I suppose, define a corresponding unit of area, the circular cm, but it does not seem to be in common use.
1000 kcmil = 1000 x 1000 cmil = 1 circular inch, since one inch is 1000 mil. The circular inch (area of a wire of diameter 1 inch) is not often used either, but it is the area of a wire 2.54 cm in diameter.
That wire would also be 2.54^2 circular cm.

When converting between kcmil areas and cm wire diameters you cannot avoid taking square roots. This makes it attractive to use a table instead. :)

For example, an area of 4 circular cm will be a diameter of 2 cm.
 
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zcanyonboltz

Senior Member
Location
denver
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Originally Posted by zcanyonboltz
How do you convert 1200 kcmil to mil. I'm multiplying 1200 by 10 to get 12,000 which multiplied by 12.5% gives me 150,000cm
I'm not sure what to multiply cm by to get kcmil or what to divide kcmil mil by to cm? Thanks

3 phase conductors of 400 kcmil conductors= 1200 kcmil x 12.5% =150,000cm
Chapter 9 table 8 150,000 cm = 3/0 THW Cu.
250.102 (C) (1)

1/0 = 105,600 cm x 2 = 211,200 cm would this be 211 kcmil?



What is the bold part?

I got this from a question .. What size grounded conductor is required for 120/208V 3 phase 4 wire service which consists of two parallel 1/0 AWG THW conductors per phase?

I used Chapter 9 Table 8 to get 1/0 AWG has a size of 105,600 cm x 2 = 211,200 cm. Then I went to Table 250.102 (C) (1) 211,200 cm = " Over 3/0 thru 350 kcmil= AWG 2 Cu grounded conductor.

 
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