Last updated on August 14th, 2022 at 01:27 pm
Choosing the correct wire size is a matter of cruciality. It is essential not only for safety reasons but also for the proper functioning of the entire electrical setup.
The correct wire size for a circuit or a ground-run depends mainly on the electrical load it intends to carry and the distance it is to run over. So, what size of wire do you need for 30 amps, 200 feet?
A 4 AWG wire is ideal for conducting 30 amps of current over 200 feet. You might even opt for a 3 AWG wire if you wish because the more influential the diameter, the more amount of electricity It can convey. However, some people would argue that a 10 AWG copper wire is the minimum diameter for 200 feet run, and a 4 AWG wire is the maximum diameter length.
What Gauge Wire Do I Need for 200 feet?

If copper is the wire material, you can use a wire of 4 AWG. However, if aluminum happens to be the wire material, a wire of 300 Kcmil works best.
In the long run of 200 feet, you must consider the wire diameter. Underground cable runs are more complicated and require thicker wires and more experience during installation than the normal household wiring.
The wire material used in a 200 feet run also helps to determine the most appropriate wire gauge. Copper and aluminum are the most common conductors used to make electrical wires.
Aluminum is relatively cheaper than copper and is a good conductor, but copper remains the best option for safety, stability, and durability.
When it comes to underground wiring, aluminum may not be your best option. It contains highly reactive particles with earth’s chemicals, which can cause it to erode quickly.
Aside from this, aluminum is costly when exposed to heat. However, it can last underground too close to a hundred years when adequately coated and bonded.
As much as a 4 AWG wire is ideal for a 200 feet cable run, you can use a big wire in its stead.
This would help reduce the voltage drop and improve your equipment’s efficiency. It also offers you the opportunity to increase the amperage later, if you so desire.
How Far Can You Run a 10 Gauge Wire for 30 amps?

You can run a ten gauge wire for 30 amps as far as 128 feet and no more. Farther distances would require thicker wires.
A 10 gauge wire is 102 inches thick and is only meant for short runs on minimal amperage.
You can use a ten gauge wire on a 20 amp circuit if it exceeds the 128 feet distance. For example, a 10 gauge copper wire would go farther than a ten gauge aluminum wire.
Most people use copper for their home wiring, especially if they intend to have heavyweight appliances.
This is because aluminum, when imposed with a massive load, can use a threat of electrical fire.
Capacity (CuFt) = Height (ft)×Width (ft) ×Depth (ft)
=4×3×2
=24CuFt
Although 128 feet is the maximum a ten gauge wire can run on 30 amps, it works best within 100 feet. The farther the distance, the less load or should be made to carry.
What Would Happen If I Use A Smaller Wire?

When it comes to wires, the thicker, the better, there’s no downside to a thick wire at all, except that it is more expensive than the thinner ones. However, the use matches the price.
Bigger wires are designed to handle the maximum current. On the other hand, smaller wires quickly show signs of strain when they encounter massive loads.
Choosing the correct wire size requires much care and experience. This task should be left for professionals to deal with.
Many hazards could emanate from improper wire size or installation; some include:
#1. Fire outbreak
Thin wires pose a high threat of starting electrical fires that spiral out of control and raze down the entire building.
Circuit breakers may not curb these fires due to the massive strain and overload.
An explosion may even occur (although it rarely does). A fire outbreak is the worst possible outcome of using thin wires.
#2. Melting

The heavy current generates a high amount of heat which outweighs the tolerance capacities of thin wires. The generated heat will, in due time, cause the wires to melt.
#3. Can Wreck Appliances
These wires can cause damages to the appliances being powered by the 30 amp circuit.
When the appliance does not get sufficient electricity, it affects their performance, and eventually, they would get damaged entirely.
#4. Voltage drop
Massive load on thin wires will overpower it and cause a voltage drop that can damage the entire setting. Unfortunately, a voltage drop is a common occurrence.
Nevertheless, when the current drops more than 4%, it is an eminent sign of a fault from the wiring.
#5. Wear and Tear
The strain caused by the excessive flow of current can lead to the wear and tear of the wires. If exposed, these wires pose many threats, from electric shocks to fire outbreaks.
Both copper and aluminum wires are susceptible to wear and tear due to thinness. However, aluminum may be more prone due to its lightweight dress.
How Do I Determine The Right Wire Gauge?
The gauge of a wire connotes its thickness and diameter. In addition, it helps in deducing the amount of current the wire can conduct.
The American Wire Gauge (AWG) is a system of numbers that denote the different wire sizes. Each gauge size has a 26% difference from the next.
The higher the gauge size, the smaller the wire. This is to say that a wire of 6 AWG is more significant than a 10 AWG wire.
The more the amperage, the thicker the wire; more current will require thicker and bigger wires.
A 10 gauge wire is suitable for 30 amps. A 40 gauge amp would need a thicker wire of 8 AWG to handle its current. Sixty amps would require a 4 AWG wire.
Minimal wind such as 20 amps can do with a 12 AWG wire. The distance to be run also plays a role in determining the correct wire gauge.
Long runs require thicker wires to conduct electricity flow over long distances efficiently. Copper wires convey more current than aluminum, making them the best option for long-run wiring.
While it is possible to determine and correctly connect all your wires effectively, it is advisable to seek trained help to avoid complications that may arise due to a blunder or misstep on your part.
Conclusion
Wires come in different sizes, and each of these sizes best serves a different purpose from the other.
Before choosing the correct wire size, calculations have to be made on the total electrical load it intends to carry.
A 200 feet distance is a long run and, as such, would require a wire of adequate thickness. A 4 AWG wire best fits this distance.
Copper wires should remain your best option for long-run wiring as aluminum wires, though inexpensive, come with many complications.
Thinner wires are best for short runs and lightweight applications. On the other hand, Thick wires are best for long runs and heavyweight applications.
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