With all the wire types around, it can get confusing, I am here to discuss one of the more fascinating types of wires, the 10/3 gauge wire comes with many benefits. We will discuss those benefits in this post and clarify what 10 3 wire is used for.
In general, 10/3 cable comes with three 10 gauge conducting wires, and a 10 gauge ground wire. That means the 10/3 cable has a total of four wires. This cable is commonly used for 220V four-pronged outlets. You can find this 10/3 wire cable in air conditioners, small kitchen ranges, and power clothes dryers.
Must-Know Things about the 10/3 Gauge Wire

If you are not familiar with 10/3 cable, this section might be valuable for you. a 10/3 cable has three different conducting wires and a ground wire. All four wires have a gauge of 10.

The 10-gauge wire is thicker than the 14 and 12-gauge wires. Therefore, the 10/3 cable has thicker wire than the 12/2 cable. Here are some other interesting facts about 10/3 wire cables.
As you already know, 10 is the gauge, and 3 represents the number of conductor wires that the cable has. This excludes the ground wire. Usually, a 10/3 cable comes with two hot wires that are colored red and black. The white one is the neutral wire and the ground wire is green.

Keep in mind: The ground wire does not always come with green insulation. Sometimes, you’ll get a bare copper wire.
Difference Between 10/3 and 10/2 Cable?
As you already know, 10/ 3 cable has four wires. But, when it comes to the 10/2 cable, it only has three wires. These wires consist of a white neutral wire, green ground wire, and a black hot wire. Even though the cable diameter is different, the wire sizes are the same.
What is 10/3 Wire Used For?

The 10/3 cable is the perfect option for 220V, 30 amp outlets. This 220V four-pronged outlet is highly useful for electrical dryers, air conditioning units, stoves, and small ovens.
Why are Four-Pronged Outlets so Special?

These four-pronged outlets can be wired to run 120V or 240V circuits. For instance, a 120V circuit powers the dryer’s sensors, timers, and other electronics. The 240V circuit powers the heating elements. (1)

Tip: If the appliances need more than 30 amps, the 10/3 cable is not enough for that outlet. So, use cables such as 6/3 or 8/3. Both 6/3 and 8/3 have thicker wire sizes compared to 10/3.
What is the Diameter of 10/3 Wire?
The 10/3 cable has a diameter of 0.66 inches. Also, a 10 gauge wire has a diameter of 0.1019 inches. The diameter of the 10/3 cable is equal to the diameter of the four 10 gauge wires, the insulation of those wires, and the cable jacket.
However, if the ground wire does not have insulation (bare copper wire), the cable diameter might be reduced accordingly.
Keep in mind: The diameter of the cable might vary based on the materials, manufacturer, and ground wire insulation.
Is 10/3 Wire Heavy Enough for a Dryer?
For most dryers, 10/3 wire is a good option, given that the dryer needs 30 amps or less. So, check the amperage before connecting your dryer to the 10/3 cable and ensure the 220V four-pronged outlet is ready.
Tip: Overloading of the electrical current can cause a tripped circuit breaker, or sometimes it might cause an electrical fire. So, always follow the above guidelines when you use 10/3 cable.
Voltage Drop of the 10/3 Cable
Before connecting the 10/3 cable to your dryer, it is always better to check the voltage drop. If we consider the maximum 3% voltage drop.
For 120V single phase, 30 amp power supply:

10 AWG wire is capable of traveling the current 58 feet without exceeding the voltage drop limits. Try to keep it around 50 feet.
For 240V single phase, 30 amp power supply:

10 AWG wire is capable of traveling the current 115 feet without exceeding the voltage drop limits. Try to keep it around 100 feet.
Click here for the Voltage Drop Calculator.
Can 10/3 Wire Be Run Underground?

Yes, for underground use, 10/3 cable is an excellent choice. However, to run a 10/3 cable underground, you’ll need two things.
- 10/3 UF cable
- Conduits
First, if you plan to bury the wire, you’ll need a few conduits. Then, buy a 10/3 wire that has underground feeder capabilities. These wires are specially designed for underground use. Usually, the UF wires are embedded together with the help of solid thermoplastic. Here are some important factors to consider while burying the 10/3 UF wire.
- Consider the voltage drop. it should be below 3%.
- If you are burying the wire with conduits, bury them at least 18 inches.
- If you are burying the wire directly, bury it at least 24 inches.
How Many Outlets Can You Put On a 10/3 Wire?
The 10/3 wire is capable of carrying 30 amp power. However, according to the NEC, you can only set up one 30 amp outlet for a 30 amp circuit.
How Many Outlets for 20 amp Circuit?
According to the NEC, any given circuit should be exposed to 80% or less load. So, if we consider this,
20 amp × 80% = 16 amp
Power requirement of a single outlet = 1.5 amp
Therefore,
Number of outlets = 10
In a 20 amp circuit, you can run ten 1.5 amp outlets.
Wrapping Up
Without a doubt, the 10/3 cable is a perfect choice for 30 amp outlets and circuits. But, keep in mind, whenever you use a 10/3 cable, take the necessary safety precaution. You are dealing with a considerable amount of electricity. So, any miscalculation might lead to a fatal accident. (2)
Take a look at some of our related articles below.
- What gauge wire from battery to starter
- Which wire is hot when both are same color
- Is white wire positive or negative
References
(1) heating elements – https://www.tutorialspoint.com/materials-used-for-heating-elements-and-the-causes-of-their-failure
(2) accident – https://www.business.com/articles/workplace-accidents-how-to-avoid-them-and-what-to-do-when-they-happen/
Video References
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