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Kevin, Licensed Electrical Contractor
Category: Electrical
Satisfied Customers: 3727
Experience:  30 years Licensed Electrical Contractor in Illinois, Adjunct College Electrical Instructor, Former Electrical Inspector, Diploma: Digital Electronics, FCC Technician License
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i need to lay an underground line for my shed a distance of

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i need to lay an underground line for my shed a distance of 250m away was wondering what size cable i should use name is XXXXX XXXXX I will be happy to assist you with your electrical question. My goal is to exceed your expectations on Just Answer!


1) Can you provide me with the voltage and the amperage of the LOAD?


2) Will you be using aluminum or copper cable?

Customer: replied 4 years ago.

240 v as for amprage not sure will need to run a 200 amp welder as well as lights grinders etc

1) Thanks for the replies Ian


2) I have calculated the voltage drop using a 240 VAC Single Phase line voltage ,a 200 amp LOAD and 250 meters (820 feet) as follows:


2A) Using aluminum conductors, this results in a 2.8% voltage drop or 6.6 volts using 900kcm conductors.


2B) Using copper conductors, this results in a 2.8% voltage drop or 6.8 volts using 600kcm conductors


3) It is recommended to maintain the voltage drop less than 3%.


4) Due to the length of the cable run and a high amperage load of 200 amps, the use of aluminum conductors will be more cost efficient versus copper conductors.





Hope this helps.........If you have any additional questions, let me know and I'll be glad to answer them for you.


Otherwise, don't forget to rate me before you log Off.

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Ian..... I see that you are in Australia and your wire sizes and voltage tolerances are different than what we use in the US. I will opt out of the question and another expert will be able to provide you with your cable sizes.

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