Voltage Drop: Chapter 9, Table 8 Method

Voltage Drop Calculations:

3Ø Phase Voltage Drop, "VD" = (1.732 x R x I x L) / 1000

1Ø Phase, and DC, Voltage Drop, "VD" = (2 x R x I x L) / 1000

Feet Meters

Stranded

Amperage, "I"
Length in Feet, "L"
2000 kcmil 1750 kcmil 1500 kcmil 1250 kcmil 1000 kcmil 900 kcmil 800 kcmil 750 kcmil 700 kcmil 600 kcmil 500 kcmil 400 kcmil 350 kcmil 300 kcmil 250 kcmil 4/O, 211600 CM 3/O, 167800 CM 2/O, 133100 CM 1/O, 105600 CM 1 AWG, 83690 CM 2 AWG, 66360 CM 3 AWG, 52620 CM 4 AWG, 41740 CM 6 AWG, 26240 CM 8 AWG, 16510 CM 10 AWG, 10380 CM 12 AWG, 6530 CM 14 AWG, 4110 CM 16 AWG, 2580 CM 18 AWG, 1620 CM Choose Wire Size, "CM"

3Ø VD for Uncoated Copper = 10.886 Volts = (1.732 x 0.0967 x 65 x 1000) / 1000
3Ø VD for Coated (Tinned) Copper = 11.371 Volts = (1.732 x 0.101 x 65 x 1000) / 1000
3Ø VD for Aluminum = 17.9 Volts = (1.732 x 0.159 x 65 x 1000) / 1000

1Ø VD for Copper = 12.571 Volts = (2 x 0.0967 x 65 x 1000) / 1000
1Ø VD for Coated (Tinned) Copper = 13.13 Volts = (2 x 0.101 x 65 x 1000) / 1000
1Ø VD for Aluminum = 20.67 Volts = (2 x 0.159 x 65 x 1000) / 1000

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Voltage at Source, "E"

Percent Voltage Drop = (VD / E) x 100

3Ø Percent VD for Uncoated Copper = 2.37 % = (10.886 / 460) x 100
3Ø Percent VD for Coated (Tinned) Copper = 2.47 % = (11.371 / 460) x 100
3Ø Percent VD for Aluminum = 3.89 % = (17.9 / 460) x 100

1Ø Percent VD for Uncoated Copper = 2.73 % = (12.571 / 460) x 100
1Ø Percent VD for Coated (Tinned) Copper = 2.85 % = (13.13 / 460) x 100
1Ø Percent VD for Aluminum = 4.49 % = (20.67 / 460) x 100

Voltage at Load = E - VD

3Ø Voltage at Load for Uncoated Copper = 449.114 VAC = 460 - 10.886
3Ø Voltage at Load for Coated (Tinned) Copper = 448.629 VAC = 460 - 11.371
3Ø Voltage at Load for Aluminum = 442.1 VAC = 460 - 17.9

1Ø Voltage at Load for Uncoated Copper = 447.429 Volts = 460 - 12.571
1Ø Voltage at Load for Coated (Tinned) Copper = 446.87 Volts = 460 - 13.13
1Ø Voltage at Load for Aluminum = 439.33 Volts = 460 - 20.67

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Temperature Correction Calculations:

R₂ = R₁ [1 + 0.00323(T₂ - 75)] for Copper Conductors
R₂ = R₁ [1 + 0.00330(T₂ - 75)] for Aluminum Conductors

Chapter 9, Table 8 calculations are based on conductors at 75ºC. If you would like to see how the values change when the temperature changes, enter a new temperature value in the input box below. Remember that (ºF - 32) / 1.8 = ºC.

New Temperature in ºC, "T₂"

3Ø Temp Corrected VD for Uncoated Copper = 9.029 Volts = (1.732 x 0.0802 x 65 x 1000) / 1000
3Ø Temp Corrected VD for Coated (Tinned) Copper = 9.434 Volts = (1.732 x 0.0838 x 65 x 1000) / 1000
3Ø Temp Corrected VD for Aluminum = 14.782 Volts = (1.732 x 0.1313 x 65 x 1000) / 1000

1Ø Temp Corrected VD for Copper = 10.426 Volts = (2 x 0.0802 x 65 x 1000) / 1000
1Ø Temp Corrected VD for Coated (Tinned) Copper = 10.894 Volts = (2 x 0.0838 x 65 x 1000) / 1000
1Ø Temp Corrected VD for Aluminum = 17.069 Volts = (2 x 0.1313 x 65 x 1000) / 1000