# Wire resistance calculation

Discussion in 'General Electronics Chat' started by ajitnayak87, Aug 24, 2015.

1. ### ajitnayak87 Thread Starter New Member

Dec 30, 2013
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0
Dear all,

I am trying to impliment the online calculator on excel sheet.
here is online calculator
http://www.bulkwire.com/wireresistance.asp

i follwed below method to calculate but i cant getting same answer http://www.rapidtables.com/calc/wire/voltage-drop-calculator.htm

can some one explain how to get value using below perameter as example

length of cable is= 50 feet

source voltage =12v

consider 24 guaze wire perameter

diameter in inch given=0.0232 inch

diameter in mm is given as=0.590mm

resistance @77 deg F=26.18 ohm/ft

resistance @77 deg F= 85.9 ohm/km

how to calculate resistance for length;voltage drop; % voltage drop??

what are right perameter to be used to exact answers

2. ### DickCappels Moderator

Aug 21, 2008
2,779
674
resistance of a length of wire in ohms = (ohms/meter) x (length or wire in meters)

voltage drop across length or wife = (resistance or length of wire) x current

% voltage drop = 100x ( voltage drop across length) / total applied voltage)

The resistance in feet should be 26.18 ohms/1,000 feet

Your task will be easier if you choose one measurement system or another and stick with it. Ohms per km @ 77 °F looks kind of funny.

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3. ### ajitnayak87 Thread Starter New Member

Dec 30, 2013
8
0
The resistance in feet should be 26.18 ohms/1,000 feet

Ok i am mentioned as defined in link. I dont know which value being used in calculator link . So I told using these perameter from link how can i get

output data :
resistance for length=1.30912
voltage drop =7.85472
out put voltage source drop=4.14
percentage loss= 65.46

Input parameter in calculator are

length of cable is= 50 feet

source voltage =12v
http://www.bulkwire.com/wireresistance.asp

4. ### gerty AAC Fanatic!

Aug 30, 2007
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5. ### ronv AAC Fanatic!

Nov 12, 2008
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You cannot calculate it because the wire resistance is to high to allow 6 amps to flow at 12 volts.
The resistance of 100 feet of 24 awg is about 2.6 ohms so the most you could get with 12 volts is about 4.6 amps.

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6. ### crutschow Expert

Mar 14, 2008
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You need a lot larger wire than 24 gauge to carry 6A for 50 feet with a reasonably small voltage drop.

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7. ### #12 Expert

Nov 30, 2010
16,705
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Is there an app for that?

Today's kids!

8. ### djsfantasi AAC Fanatic!

Apr 11, 2010
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I'm still amazed at Dick's voltage drop across length or wife

9. ### Alec_t AAC Fanatic!

Sep 17, 2013
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Don't most wives offer resistance? .

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10. ### DickCappels Moderator

Aug 21, 2008
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674
Don't get me started on that subject...

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11. ### Gdrumm Distinguished Member

Aug 29, 2008
684
36
You guys crack me up

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Nov 12, 2008
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