Physics Calculators ▶ Voltage Drop Calculator
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The free voltage drop calculator is intended to help you in determining the voltage drop across a wire piece. Based on the data from NEC and Wire Resistance terminology, this volt drop calculator DC will show you various parameters that will be good to know while installing energy lines for residential or commercial purposes.
Now it’s time to move by and discuss the voltage loss calculation concept in proper detail.
Let’s get down to the topic!
In the field of electrical energy transmission:
“The overall loss of the voltage due to the internal impedance of the circuit is known as the voltage drop”
In the above figure, we have a voltage applied to a circuit network containing only a resistance. Now when the current will pass through the resistance, there will be a drop in voltage from one end to the other end of the resistor. This drop is actually the voltage drop that could be instantly determined by using this voltage calculator.
Just make a supposition about the water pipe having a hose at its one end. The reason why we are considering it here is its best match to the voltage drop terminology. Here:
Here this best wire voltage drop calculator is the best method that assists you to determine the voltage drop across any conductor, no matter how sharp the opposition is!
According to the IEEE(Institute of Electrical and Electronics Engineers), there are basically a couple of kinds of voltage drop. It is mainly due to the direction of the current flowing through an electrical circuit. Let’s discuss them one by one!
Positive drop in the voltage occurs when the electronic current flows through the circuit.
The current from the negative terminal of the circuit to its positive terminal is termed electronic current.
This voltage drop usually occurs in a circuit when there is conventional current flowing through it.
This specific current is flown from an area of high potential to the area of low potential in an electric circuit.
For AC and DC voltages, we have different formulas depending upon the phase system that is in use. You must be capable of determining the drops across the voltages and other electricity related parameters. And for this purpose, you must have a sound grip over the following expressions:
$$ V_{drop\left(V\right)} = I_{wire\left(A\right)} * R_{wire\left(Ω\right)} $$
$$ V_{drop\left(V\right)} = I_{wire\left(A\right)} * \left(2 * L_{\left(ft\right)} * \frac{R_{wire\left(\frac{Ω}{kft}\right)}}{1000_{\left(\frac{ft}{kft}\right)}}\right) $$
$$ V_{drop\left(V\right)} = I_{wire\left(A\right)} * R_{wire\left(Ω\right)} $$
$$ V_{drop\left(V\right)} = I_{wire\left(A\right)} * \left(2 * L_{\left(m\right)} * \frac{R_{wire\left(\frac{Ω}{km}\right)}}{1000_{\left(\frac{m}{km}\right)}}\right) $$
$$ V_{drop\left(V\right)} = \sqrt{3} * I_{wire\left(A\right)} * R_{wire\left(Ω\right)} $$
$$ V_{drop\left(V\right)} = 1.732 * I_{wire\left(A\right)} * \left(L_{\left(ft\right)} * \frac{R_{wire\left(\frac{Ω}{kft}\right)}}{1000_{\left(\frac{ft}{kft}\right)}}\right) $$
$$ V_{drop\left(V\right)} = \sqrt{3} * I_{wire\left(A\right)} * R_{wire\left(Ω\right)} $$
$$ V_{drop\left(V\right)} = 1.732 * I_{wire\left(A\right)} * \left(L_{\left(m\right)} * \frac{R_{wire\left(\frac{Ω}{km}\right)}}{1000_{\left(\frac{m}{km}\right)}}\right) $$
Whatever the phase is, our free voltage drop calculator will take a couple of seconds to display the actual loss in the voltage transmission.
For a wire having a diameter in inches and n gauges:
$$ d_{n\left(in\right)} = 0.005 inches * 92^{\frac{\left(36n\right)}{39}} $$
And when the diameter is in millimetres:
$$ d_{n\left(mm\right)} = 0.127 mm * 92^{\frac{\left(36n\right)}{39}} $$
$$ A_{n\left(kcmil\right)} = 1000 * d_{n}^{2} = 0.025 in^{2} * 92^{\frac{\left(36n\right)}{19.5}} $$
$$ A_{n\left(in^{2}\right)} = \left(\frac{\pi}{4}\right) * d_{n}^{2} = 0.000019635 in^{2} * 92^{\frac{\left(36n\right)}{19.5}} $$
$$ A_{n\left(mm^{2}\right)} = \left(\frac{\pi}{4}\right) * d_{n}^{2} = 0.000019635 mm^{2} * 92^{\frac{\left(36n\right)}{19.5}} $$
$$ R_{n\left(\frac{Ω}{kft}\right)} = 0.3048 * 10^{9} * \frac{ρ\left(Ω.m\right)}{25.4^{2} * A_{n\left(in^{2}\right)}} $$
There can be many causes of the voltage drop. But most highlighted of them are enclosed in this section. So let’s give a read!
This is indeed the most important factor that helps you to avoid any voltage issues within your residential or commercial supply. Many conductive materials are there in use but the best and affordable among them include copper and iron. Among these two, copper is more reliable because its voltage drop drop capacity is less than the iron. Furthermore, you can also verify the fact by using this best voltage drop calculator. Below we have a table that throws a light on significant properties of different conductive materials that are being used in the market:
Electric conductivity (10.E6 Siemens/m)  Electric resistivity (10.E8 Ohms.m)  Thermal conductivity (W/m.K)  Thermal expansion factor 10E6(K1) de 0 à 100°C  Density (g/cm3)  Melting or deterioration temperature (°C)  
Silver  62,1  1,6  420  19,1  10,5 
961 
Copper 
58,7  1,7  386  17  8,9  1083 
Gold  44,2  2,3  317  14,1  19,4 
1064 
Aluminium 
36,9  2,7  237  23,5  2,7  660 
Molybdenum  18,7  5,34  138  4,8  10,2 
2623 
Zinc 
16,6  6,0  116  31  7,1  419 
Lithium  10,8  9,3  84,7  56  0,54 
181 
Brass 
15,9  6,3  150  20  8,5  900 
Nickel  14,3  7,0  91  13,3  8,8 
1455 
Steel 
10,1  9,9  80  12,1  7,9  1528 
Palladium  9,5  10,5  72  11  12 
1555 
Platinium 
9,3  10,8  107  9  21,4  1772 
Tungsten  8,9  11,2  174  4,5  19,3 
3422 
Tin 
8,7  11,5  67  23,5  7,3  232 
Bronze 67Cu33Sn  7,4  13,5  85  17 
8,8 
1040 
Carbone steel 
5,9  16,9  54  12  7,7  1400 
Carbone  5,9  16,9  129  0,2  1,8 
2500 
Lead 
4,7  21,3  35  29  11,3  327 
Titanium  2,4  41,7  21  8,9  4,5 
1668 
Stainless steel 316L EN1.4404 
1,32  76,0  15  16,5  7,9  1535 
Stainless steel 304 EN1.4301  1,37  73,0  16,3  16,5  7,9 
1450 
Stainless steel 310 EN1.4841 
1,28  78  14,2  17  7,75  2650 
Mercury  1,1  90,9  8  61  13,5 
39 
FeCrAl 
0,74  134  16  11,1  7,2 
+1440 
Length and diameter are two factors that contribute to the voltage drop. Here the most remarkable fact to consider is that the wire having large lengths will have low drop in voltage when compared to the wires of smaller lengths.
AWG System is specifically developed by American Electrical Industry and it helps you to estimate the diameters of the round conductor wires of various lengths and sizes. The following table contains the standard diameters of the wires most widely used by consumers:
AWG 
Diameter 
Turns of wire  Area  Copper resistance  
inch  mm  per inch  per cm  kcmil  mm2  Ω/km 
Ω/1000ft 

0000 (4/0) 
0.4600  11.684  2.17  0.856  212  107  0.1608  0.04901 
000 (3/0)  0.4096  10.404  2.44  0.961  168  85.0  0.2028 
0.06180 
00 (2/0) 
0.3648  9.266  2.74  1.08  133  67.4  0.2557  0.07793 
0 (1/0)  0.3249  8.252  3.08  1.21  106  53.5  0.3224 
0.09827 
1 
0.2893  7.348  3.46  1.36  83.7  42.4  0.4066  0.1239 
2  0.2576  6.544  3.88  1.53  66.4  33.6  0.5127 
0.1563 
3 
0.2294  5.827  4.36  1.72  52.6  26.7  0.6465  0.1970 
4  0.2043  5.189  4.89  1.93  41.7  21.2  0.8152 
0.2485 
5 
0.1819  4.621  5.50  2.16  33.1  16.8  1.028  0.3133 
6  0.1620  4.115  6.17  2.43  26.3  13.3  1.296 
0.3951 
7 
0.1443  3.665  6.93  2.73  20.8  10.5  1.634  0.4982 
8  0.1285  3.264  7.78  3.06  16.5  8.37  2.061 
0.6282 
9 
0.1144  2.906  8.74  3.44  13.1  6.63  2.599  0.7921 
10  0.1019  2.588  9.81  3.86  10.4  5.26  3.277 
0.9989 
11 
0.0907  2.305  11.0  4.34  8.23  4.17  4.132  1.260 
12  0.0808  2.053  12.4  4.87  6.53  3.31  5.211 
1.588 
13 
0.0720  1.828  13.9  5.47  5.18  2.62  6.571  2.003 
14  0.0641  1.628  15.6  6.14  4.11  2.08  8.286 
2.525 
15 
0.0571  1.450  17.5  6.90  3.26  1.65  10.45  3.184 
16  0.0508  1.291  19.7  7.75  2.58  1.31  13.17 
4.016 
17 
0.0453  1.150  22.1  8.70  2.05  1.04  16.61  5.064 
18  0.0403  1.024  24.8  9.77  1.62  0.823  20.95 
6.385 
19 
0.0359  0.912  27.9  11.0  1.29  0.653  26.42  8.051 
20  0.0320  0.812  31.3  12.3  1.02  0.518  33.31 
10.15 
21 
0.0285  0.723  35.1  13.8  0.810  0.410  42.00  12.80 
22  0.0253  0.644  39.5  15.5  0.642  0.326  52.96 
16.14 
23 
0.0226  0.573  44.3  17.4  0.509  0.258  66.79  20.36 
24  0.0201  0.511  49.7  19.6  0.404  0.205  84.22 
25.67 
25 
0.0179  0.455  55.9  22.0  0.320  0.162  106.2  32.37 
26  0.0159  0.405  62.7  24.7  0.254  0.129  133.9 
40.81 
27 
0.0142  0.361  70.4  27.7  0.202  0.102  168.9  51.47 
28  0.0126  0.321  79.1  31.1  0.160  0.0810  212.9 
64.90 
29 
0.0113  0.286  88.8  35.0  0.127  0.0642  268.5  81.84 
30  0.0100  0.255  99.7  39.3  0.101  0.0509  338.6 
103.2 
31 
0.00893  0.227  112  44.1  0.0797  0.0404  426.9  130.1 
32  0.00795  0.202  126  49.5  0.0632  0.0320  538.3 
164.1 
33 
0.00708  0.180  141  55.6  0.0501  0.0254  678.8  206.9 
34  0.00630  0.160  159  62.4  0.0398  0.0201  856.0 
260.9 
35 
0.00561  0.143  178  70.1  0.0315  0.0160  1079  329.0 
36  0.00500  0.127  200  78.7  0.0250  0.0127  1361 
414.8 
37 
0.00445  0.113  225  88.4  0.0198  0.0100  1716  523.1 
38  0.00397  0.101  252  99.3  0.0157  0.00797  2164 
659.6 
39 
0.00353  0.0897  283  111  0.0125  0.00632  2729  831.8 
40  0.00314  0.0799  318  125  0.00989  0.00501  3441 
1049 
The amount of electrons flowing through a wire is directly proportional to the voltage drop occurring in it. This current capacity, when it reaches its peak, is referred to as the ampacity of the conductor. You can use a free voltage calculator to check how maximum amperes will affect the voltage being transmitted.The electricity cost can be controlled by measuring the overall voltage and the total appliances installation in your apartment. The electricity cost calculator can be handy in regulating your electric cost per month.
Below here we have a proper tables that provide a whole concept of the voltage changes depending upon the length of the wires. Let’s have a look at these!
120 Volt, Conductor size (AWG or kcmil) Single Phase, Max 3% Voltage Drop* 

Length of Run 

25′  50′  100′  150′  200′  
Copper  14  12  10  8  6 
15 AMP** 
Copper 
12  12  8  6  4  20 AMP** 
Copper  10  10  6  4  4 
30 AMP** 
Copper 
1  1  1  2/0  4/0  100 AMP** 
Aluminium  1/0  1/0  2/0  4/0  300 MCM 
100 AMP** 
Copper 
3/0  3/0  3/0  300 MCM  500 MCM  200 AMP*** 
Aluminium  250 MCM  250 MCM  300 MCM  600 MCM  900 MCM 
200 AMP*** 
240 Volt, Conductor Size (AWG or kcmil) Single Phase, Max 3% Voltage Drop* 

Length of Run 

25′  50′  100′  150′  200  
Copper  14  14  12  10  10 
15 AMP** 
Copper 
12  12  12  10  8  20 AMP** 
Copper  10  10  10  8  6 
30 AMP** 
Aluminium 
8  8  8  6  4  30 AMP** 
Copper  8  8  8  6  4 
40 AMP** 
Aluminium 
6  6  6  4  3  40 AMP** 
Copper  6  6  6  6  4 
50 AMP** 
Aluminium 
4  4  4  4  2 
50 AMP** 
You can also verify all these values by subjecting to our free dc voltage drop calculator.
Let’s resolve an example to clear your mind about the voltage drop. Just stay focused!
Example Problem:
How to calculate voltage drop in a series circuit having ampacity of 56 amps and opposition to it as 43 ohms?
Solution:
Using voltage drop calculation formula:
$$ V_{drop\left(V\right)} = I_{wire\left(A\right)} * R_{wire\left(Ω\right)} $$
$$ V_{drop\left(V\right)} = 56 * 43 $$
$$ V_{drop\left(V\right)} = 2.4 V $$ (For calculations, tap Ohm’s Law Calculator)
Get going through the usage guide of this voltage loss calculator that will let you observe various electrical elements in a couple of clicks.
Input:
If you selected the “Estimated Voltage”:
If you selected the “NEC Data”:
If you selected the “Other Parameters”:
Output:
The free voltage calculator does the following calculations in seconds:
When the potential at the final end of the wire gets higher than the potential at the start, then it gives rise to the voltage drop that could be judged with this voltage drop calculator.
When you are interested in transmitting the voltage over long distances, then the length of the wire would be enhanced. This increase will be directly proportional to the resistance and when the resiste\ance increases, the voltage drop will also get maximum. That is why very long voltage transmission losses more voltage. This fact can also be analysed by a volt drop calculator.
Following are the precautions that you can take in order to minimise the voltage drop in a line. Theses include:
The overall decrease in the final voltage can also be calculated by this voltage calculator.
The voltage across the conductive material is the actual voltage flowing through it. While on the other hand, the voltage drop is the voltage that is provided by any external device or electrical circuit connected.
If we recall Ohm’s law and keep the resistance of the linear circuit as fixed, then a reasonable increase in the voltage will also increase the overall current and vice versa.
The maximum voltage loss calculation that could be tolerable between a feeder conductor to the farthest load connected in series or parallel must not exceed the value of the 5%.
When a battery is connected to a load of certain power, voltage drop occurs in it. This is due to the chemical reactions taking place in the battery that produces the electricity. When the current gets increased more and more, the flow of electrons from one electrode of the battery to the other also gets increased.
Potential drops are caused in the presence of the ground. But voltage drops are the drop caused by the current facing some amount of reasonable resistance. You can also measure this drop in any circuit network with this wiring voltage drop calculator.
When the voltage gets too low, the amperage increases enough to melt down the electrical conductors. This causes abnormality in the functioning of the load devices.
According to the solar industry lexicon, the voltage drop must be controlled so as it could not increase the 2% at its maximum. This behaviour can be checked by this voltage calculator in a fragment of seconds.
For a single phase line, the maximum drop that is acceptable is around 230.4V. While in case of a three phase system, the drop at its minimum must be 398.4V.
This particular test can be used to diagnose problems that are caused in a circuit due to the high resistances. And you can perform the voltage drop test by either of the two ways below:
No. Both are different. Where the alternating cables are insulated using a single coating, the direct current cables are insulated by employing double insulation.
No doubt gild is also a good conductor of electricity but it is not used due to being very expensive. Contrary to it, copper, aluminium, and iron are very cheap and effective conductors of both electricity and current.
Direct current is not used in homes because its value never becomes zero. This is very lethal as when a person accidentally touches a live wire or there is any short circuit in circuit, the voltage will not be changed and it will destroy the component or may let the person die.
From the source of Wikipedia: Voltage drop, Voltage drop in directcurrent circuits, Voltage drop in alternatingcurrent circuits
From the source of Khan Academy: Kirchhoff’s laws, Currents into a node, Resistivity and conductivity, Voltmeters and Ammeters, Electrolytic conductivity
From the source of Lumen Learning: Ohm’s Law, Resistance and Simple Circuits, Conservation of Energy