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What size wire to run 500 feet? This is a question that many people have, and the answer can vary depending on the type of wire.
Below, we will explore this for electrical applications. Also, we’re going to help you figure out the right size wire for your needs.
What Size Wire To Run 500 Feet
The size of the wire you need to use for your project, you will need to keep in mind several factors.
If your breaker box is 500 feet away from the main house, you need to use 1/0 AWG UF-B wire for a 120V circuit up to 20A.
Besides, for your 30-amp circuit would require 3/3 AWG wire.
Keep in mind that when you use a 240-volt system, then you will need to use a heavier gauge wire.
As a result, you can run multiple appliances to be used at the same time.
What Size Wire Do You Need to Use?
The longer the circuit the wire provides, the less voltage. That is called Voltage drop. As the wire releases heat, it loses electricity. If you use longer wire, more heat is lost.
When you run a cable to a shed away from your home, you may notice the effects of voltage drop devices that do not work at full power and dim the light.
Because then your 120-volt circuit becomes 108 volts or less due to voltage dropping!
Another way to compensate for this is to use thicker wire, which will decrease the current and voltage drop resistance.
Keep in mind that the thinner the wire, the more excellent its resistance – and heat loss. Make it thicker by adding more layers, allowing less resistance.
So, Let’s look at the size of wire needed to connect a circuit from your main panel in your home to your shed.
Keep in mind that the below calculations are consistent with national standards that demand a 3% voltage drop be the maximum tolerable loss in a circuit.
- For 150 feet, use 6/2 AWG wire on a 20-amp breaker (120-volt circuit on a 20-amp breaker).
- 300-foot run – a 120-volt, the 20-amp circuit would require 4/2 AWG wiring. A 240volt, 30-amp circuit would need 4/3 AWG wire.
- For 500 Feet – A 120-volt, the 20-amp circuit needs 1/0 AWG wire. A 240-volt, 30-amp circuit requires 3/3 AWG wire.
Remember that a 3% voltage drop is exceptionally low.
You won’t notice the difference if you’re using 8/2 wire for a 150-foot run to a shed on a 20-amp breaker.
Why? To deliver 20 amps, you’d have to operate several appliances simultaneously on full power.
How To Pick The Correct Size Wire For Your Project
You’ll need to consider the following factors to choose the best wire gauge for your project. So, let’s take a look!
The length Of The Circuit
At first, you need to determine the length of the circuit. The further the distance, the more voltage drop you’ll experience.
Because of this, you may need to use a larger size wire to compensate for the loss.
Additionally, the more appliances you have on the circuit, the more power you’ll need to compensate for the increased demand. So, you’ll need to use a larger size wire.
The Type of Circuit
You also need to think about the type of circuit you’re working with. If your circuit is 120-volt, you won’t need as thick of a wire as you would for a 240-volt circuit.
The reason is that the 240-volt circuit carries twice the amount of current as a 120-volt circuit.
The NEC Guidelines
Of course, you’ll also need to consider the NEC guidelines when choosing the best wire gauge for your project.
The NEC is the authority when it comes to electrical codes and standards.
According to the NEC, the minimum size of wire that can be used for a given circuit is 14 AWG for a 15-amp circuit and 12 AWG for a 20-amp circuit.
However, these are just the minimum requirements – you’re free to use a larger size wire if you want.
The Number Of Appliances On The Circuit
If you have a lot of appliances on the circuit, you may need to use a larger size wire to compensate for the increased demand.
Because the more appliances you have, the more current will be flowing through the circuit.
Additionally, remember if you’re using appliances that require a lot of power, such as hair dryers or air conditioners, you’ll need to use a thicker wire to prevent the circuit from becoming overloaded.
Amount of Power they will Draw
As we mentioned before, if you’re using appliances that require a lot of power, such as hair dryers or air conditioners, you’ll need to use a thicker wire to prevent the circuit from becoming overloaded.
Before choosing a wire gauge, you’ll need to calculate the amount of power your appliances will draw.
To do this, you’ll need to know the voltage and amperage of each appliance.
Once you have this information, you can use the following formula to calculate the wattage:
Wattage = Voltage x Amperage
For example, if you have a hair dryer that runs on 120 volts and draws 10 amps, the wattage would be 1200 watts.
As you can see, there are a lot of factors to consider when choosing the best wire gauge for your project.
However, as long as you keep all of these factors in mind, you should be able to choose the best wire gauge for your project.
Is It Possible To Use Oversized Wire?
Yes, you can use an oversized wire on your smaller circuit. The circuit breaker will shut off before the wire gets hot enough to cause a fire.
When you use the oversized wire, you won’t see any decrease or increase in the performance of your circuit.
The only advantage is that you’ll reduce the voltage drop in the circuit. Which will likely be minor, to begin with.
Also, Increases the amperage of your breaker in the future without changing the wire size by allowing more room on one circuit.
However, you cannot use a smaller wire on your larger circuit. If you do, the wire will heat up and could cause a fire.
So, make sure you always use the correct size wire for your circuit.
On the other hand, keep in mind that when you use a 240-volt system, then you will need to use a heavier gauge wire.
Also, for the 240-volt system, you will need 6/3. This is because the 240-volt system will require more power than a 120-volt system.
What Happens If Wire Gauge Is Too Small?
If you use a wire gauge that is too small, the circuit breaker will not trip because the current flowing through the wire is below the threshold that would trip the breaker. However, the wire will heat up and could cause a fire. So never use a small wire gauge.
What Happens If Wire Gauge Is Too Big?
The circuit breaker that protects the circuit will trip if you use a wire gauge that is too big. Also, the copper in the wire can handle the current without getting hot, but the insulation surrounding the conductor could overheat and catch fire. So, don’t use a wire that is too big for the circuit.
What Size Wire Do I Need For 30 Amps At 200 Feet?
In most cases, you’ll need 8-gauge wire for 30-amp 240v circuits and 6-gauge wire for 20-amp 120v circuits. The key for 30 amp is the 8-gauge thickness. The length of the wire won’t affect amperage rating, but it will affect voltage drop.
For 8-gauge wire, voltage drop should be less than 3% at 200 feet. If you have a long run or are supplying a large appliance, you may need to go up to the 6-gauge wire. You can use this voltage drop calculator to determine the appropriate gauge for your particular situation.
We hope that this article has given you a better understanding of wire gauges and how to choose the best one for your project.
Also, give you a better idea about what size wire to run 500 feet.
Remember, the most important thing is always to use the correct size wire for your circuit.