# Voltage Drop Calculator - Calculatorall.com

This voltage drop calculator allows for estimating voltage drop in electronic circuits depending on their wire size, anticipated load current, and distance. Keep it in mind that this calculator works on the assumption that circuit is operating in normal condition - normal frequency and at room temperature. Actual drop in the voltage may vary depending on wire's condition, the conduit that is used, connector, frequency, temperature, etc. It's recommended that voltage drop must be under 5% when the circuit is fully loaded.

 Wire Material: -- select -- Copper Aluminum Carbon steel Electrical steel Gold Nichrome Nickel Silver Wire Size AWG inch mm Distance* feet meters Phase DC AC - Single phase AC - Three phase Number of conductors single set of conductors 2 conductors per phase in parallel 3 conductors per phase in parallel 4 conductors per phase in parallel Voltage Load current Amps
What Causes Voltage Drop?

This voltage drop calculator allows for estimating voltage drop in electronic circuits depending on their wire size, anticipated load current, and distance. Keep it in mind that this calculator works on the assumption that circuit is operating in normal condition - normal frequency and at room temperature. Actual drop in the voltage may vary depending on wire's condition, the conduit that is used, connector, frequency, temperature, etc. It's recommended that voltage drop must be under 5% when the circuit is fully loaded.

What Causes Voltage Drop?

There are, basically, four different causes of voltage drop. This voltage drop calculator takes into account all these factors to determine the amount of voltage drop. Let's take a look at these four factors that cause voltage drop.

First of all, the material used in the wire can be a major cause of voltage drop. Copper is considered as better conductor of electricity as compared to aluminum and the wires made of copper usually have less amount of voltage drop for any given wire size and wire length. Electricity moving through copper wires is actually some electrons that are pushed forward by voltage. Higher voltage would mean there are more electrons flowing through that wire.

Another major factor that plays its part in determining the voltage drop is wire size. The wires having a bigger size (the ones with bigger diameter) usually have less amount of voltage drop as compared to smaller wires having same length. Talking about the American wire gauge, each decrease of 6 gauge gives doubling of wire diameter, while decreasing 3 gauge doubles up the cross sectional area of the wire.

The third major factor that plays its part in dropping the voltage is the length of the wire. When the length is shorter, it is synonymous to less drop in voltage. On the contrary, longer wires with same size or diameter tend to drop more of it. Such voltage drop becomes crucial when the wire’s length is too long. However, this may not be a major issue with the circuits we have in our homes. Excessive drop in voltage may result in efficiency loss when it comes to operation of motors, appliances and light. It can cause the lights to get dim while the life of appliances and motors is shortened. So, using right gauge is important when you have to run the wires over a big distance.

The last factor is the current that is being carried through the wires. It can also cause the voltage to drop. Increasing the amount of current that flows through a wire can result in an increase in the amount of voltage drop as well. The capacity of carrying current is nothing different from ampacity - the number of electrons which can actually be pushed through a wire in an instance.

What Does Ampacity Of A Wire Depend On?

There are several factors that contribute to a wire’s ampacity. There is an insulation cover on the wires and it can get damaged in case if wire’s temperature goes too high. The material used in making the wires is, obviously, a significant factor. If the wire is used for sending the alternating current, alternation speed can impact ampacity. Temperature can also have its impact on ampacity as well.

It is often observed that bundles are made to use cables. So, when the cables come together, total heat generated by them can affect ampacity as well as voltage drop. So, the strict bundling rules should be followed to avoid this.

How This Voltage Drop Calculator Works?

The voltage drop calculator that we're talking about here considers all the aforementioned factors that can have some impact on voltage. It requires you to provide a handful of values to calculate accurate drop in voltage that can be expected. The input values required include wire material, wire size, distance over which the wire will be run, phase, conductors used, load current and voltage. It is also important that you specify the appropriate units for distance and wire size.

Once you have provided all the input values, just hit the calculate button and the voltage drop calculator will show you the drop in voltage that you can expect, the percentage drop in voltage, and the voltage that you'll be getting after the drop.

So, if you are looking for a way to measure the drop in voltage for one reason or another, use this voltage drop calculator to determine the values mentioned above.