APRENDA a Usar o MULTIMETRO - Passo a passo

Summary

In this video, Ricardo from the C Eletricista channel provides a practical introduction to a basic multimeter, often the first choice for beginner electricians due to its affordability. He explains its key functions, including measuring DC and AC voltage, resistance, diodes, transistors, and testing continuity, while emphasizing proper usage and scale selection to avoid errors or device damage. Using simple demonstrations with a battery, resistor, and cable, Ricardo clarifies common misconceptions about polarity and current measurement limitations. The video offers a clear, hands-on guide for beginners to confidently use a multimeter in both electrical and electronic applications, making it an essential learning tool.

Takeaways

• 😀 The video introduces a basic multimeter that is commonly the first one electricians buy due to its affordability.
• 😀 Despite its simplicity, this multimeter has multiple functions and can perform most standard measurements.
• 😀 Care must be taken when using the dial selector, as it differs from more advanced models.
• 😀 DC voltage measurement requires connecting the red probe to positive and the black probe to negative, showing negative values if reversed.
• 😀 AC voltage measurement does not have polarity, and the multimeter should be set to a higher range (e.g., 750V) to avoid damage.
• 😀 The multimeter has current measurement functions, but the scales are very limited, making it impractical for most current measurements.
• 😀 Resistance can be measured accurately using the appropriate scale, and polarity does not matter.
• 😀 Special plugs are available for measuring transistors and diodes, but they are mostly used in electronics and not everyday electrical work.
• 😀 Continuity testing can be done by setting the multimeter to an appropriate resistance scale and checking if the reading goes close to zero.
• 😀 This multimeter is suitable for beginners because mistakes with it are less financially risky compared to more expensive models.
• 😀 Key electrical terminology: in electronics, positive and negative are used, while in general electrical work, phase and neutral are the standard terms.

Q & A

What is the primary reason many electricians start with this particular multimeter?

Many electricians start with this multimeter because it is affordable and a common entry-level choice. It provides the essential functions needed for basic electrical measurements without a high initial cost.

Why is it important to be cautious with the selector dial on this multimeter?

The selector dial on this multimeter is crucial because it controls the scale and type of measurement. Unlike other models, this one has a single scale, and switching incorrectly between settings could damage the device. Therefore, attention to the correct setting is essential.

What happens if you measure voltage in reverse with this multimeter?

If you measure voltage in reverse, the multimeter will display a negative sign, but it won't damage the device. The reading will still be accurate, showing the same voltage but with a negative sign to indicate the reverse polarity.

What should you do if you're measuring alternating voltage and you don't want to risk damaging the multimeter?

When measuring alternating voltage, always set the multimeter to the 750V range to avoid potential damage, even if the local voltage is lower, such as 110V. This ensures that the multimeter can handle higher voltage readings safely.

What is the purpose of the 200V setting on the multimeter, and why should you avoid using it for alternating voltage?

The 200V setting is too low for safely measuring high alternating voltages like 220V. Using it could lead to damage to the multimeter. Instead, always set the device to the 750V range when measuring alternating voltage.

Can this multimeter be used for measuring current, and if not, why?

This multimeter is not ideal for measuring current because its current measurement ranges are too small. For measuring current, a clamp meter or a more suitable multimeter with larger current ranges is recommended.

How does this multimeter measure resistance?

To measure resistance, set the multimeter to the appropriate resistance range, such as 20K. The multimeter can then measure the resistance of components like resistors, showing the value in ohms on the display.

What is the significance of the 'continuity' function on this multimeter, and how does it work?

The continuity function allows you to check whether a circuit is complete or if there is a break. The multimeter will show a low reading (close to zero) if the circuit is complete and a high reading (often showing '1') if there is a break.

Does this multimeter have the capability to test transistors, and if so, how is it done?

Yes, this multimeter can test transistors, but it requires a special connector for the measurement. The transistor is placed in the appropriate socket, and the multimeter will provide readings to indicate whether the transistor is functioning correctly.

What are some key limitations of this multimeter compared to more advanced models?

This multimeter has limitations, particularly in measuring current (due to its small current ranges) and some advanced features like measuring high-frequency transistors. However, for basic electrical and electronic measurements, it is sufficient and cost-effective.