Como calcular a seção do cabo pela distância, rápido e fácil !!

Summary

In this video, the process of calculating conductor section size based on voltage drop and distance is explained in a clear and practical manner. The script highlights the importance of maintaining voltage drop within the 4% limit as per NBR 5410 standards. By applying a simple formula, viewers learn how to calculate the conductor size needed to prevent excessive voltage drop, considering factors like wire length and current. An example using a 5500W shower at 220V demonstrates how to determine the right conductor size for different circuit lengths (40m and 80m).

Takeaways

• 😀 The conductor's section is calculated based on the distance and the voltage drop limit.
• 😀 Factors influencing conductor size include grouping factor, insulation temperature, installation method, and voltage drop.
• 😀 The voltage drop increases with the conductor's length, which in turn requires a larger conductor section to compensate.
• 😀 According to NBR 5410, the maximum acceptable voltage drop is 4% for terminal circuits.
• 😀 A formula can be used to calculate the appropriate conductor section based on power, voltage, and other factors.
• 😀 An example with a shower circuit is used to demonstrate how the voltage drop and conductor section are calculated.
• 😀 For a 220V supply and a 5500W power load, the project current is 25A.
• 😀 A 40-meter conductor requires a conductor section of 4mm² to maintain a 4% voltage drop.
• 😀 For an 80-meter circuit, the required conductor section increases to 10mm² to stay within the acceptable voltage drop.
• 😀 The video emphasizes the simplicity and importance of calculating conductor sections for electrical installations.
• 😀 The content encourages viewers to like and subscribe, stating that it helps the creator's channel.

Q & A

What factors influence the section size of a conductor?

The section size of a conductor is influenced by factors like the conductor's length, the permissible voltage drop, temperature, insulation type, grouping factor, and the installation method.

How does the length of a conductor affect its resistance and voltage drop?

The longer the conductor, the greater its resistance, which in turn leads to a higher voltage drop. To reduce this drop, the conductor's section must be increased.

What is the maximum allowable voltage drop according to NBR 5410 for terminal circuits?

According to NBR 5410, the voltage drop for terminal circuits must not exceed 4%.

What is the formula used to calculate the section size of a conductor?

The formula includes several factors: S = (ρ * L * I) / (V * ΔV), where S is the section size, ρ is the resistivity of copper, L is the conductor length, I is the current, V is the voltage, and ΔV is the permissible voltage drop.

How is the current for a project calculated in the given example?

In the example, the current is calculated by dividing the power (5500W) of the shower by the supply voltage (220V), resulting in a current of 25 amperes.

What is the resistivity of copper used in the calculations?

The resistivity of copper used in the calculations is 0.0172 ohm millimeters squared per meter (Ω·mm²/m).

What does the voltage drop percentage represent in the conductor sizing process?

The voltage drop percentage indicates the allowable reduction in voltage from the source to the load, which is considered when selecting the appropriate conductor size to maintain efficient operation.

In the example with a 40-meter conductor, what conductor size is required?

For a 40-meter conductor, the required conductor size is 4mm² to achieve a voltage drop of 4%.

How does the required conductor size change when the circuit length is doubled?

When the circuit length is doubled from 40 meters to 80 meters, the required conductor size increases to 10mm² to maintain a 4% voltage drop.

What is the main takeaway from the video regarding conductor sizing?

The key takeaway is that conductor sizing is influenced by the length of the conductor, the permissible voltage drop, and other factors, and it’s crucial to apply the right formulas to ensure efficient and safe electrical installations.