basic meter

Summary

In this video, the basics of using a multimeter (referred to as a 'basic meter') are explored, demonstrating how it functions as both a voltmeter and an ammeter. The tutorial walks through switching between modes, connecting the meter in parallel for voltage measurement and in series for current measurement. Key concepts include understanding scale markings, calculating measured values, and interpreting the meter’s readings. The video also explains how to calculate current and voltage values using formulas, offering practical examples with a lamp and battery circuit. It serves as a helpful guide for beginners learning to measure electrical values safely and accurately.

Takeaways

• 😀 The basic meter can function as both a voltmeter and an ammeter.
• 😀 To use the basic meter as a voltmeter, set the knob to the 'V' position, which measures electrical voltage.
• 😀 To switch to ammeter mode, turn the knob to 'A' to measure current.
• 😀 When using the ammeter function, connect the meter in series with the circuit to measure current.
• 😀 The ammeter has multiple current ranges such as 5A, 1A, 100mA, and 100µA, which determine the maximum measurable current.
• 😀 For voltage measurements, connect the meter in parallel with the circuit, with the positive terminal connected to the positive side of the circuit.
• 😀 When measuring voltage, the meter's scale and the corresponding voltage range (like 50V, 10V, 1V, or 100mV) determine the actual voltage based on the needle's position.
• 😀 For accurate voltage measurement, calculate the value based on the needle's position on the scale.
• 😀 When measuring current, the meter shows a needle reading that corresponds to a calculated value based on the selected range and the needle's position.
• 😀 To calculate the measured current or voltage, use the formula: N = (SD * SM) / BU, where N is the measured value, SD is the needle’s reading, SM is the maximum scale, and BU is the chosen range.
• 😀 The final measured value for current or voltage can be determined through interpolation if the needle falls between two scale values.

Q & A

What is the main function of a basic meter?

The basic meter has two main functions: it acts as a voltmeter to measure voltage and as an ammeter to measure current.

How do you switch the basic meter from voltmeter to ammeter?

To switch from voltmeter to ammeter, you need to turn the function selector knob so that it shows 'A' for ammeter. This will allow the meter to measure current.

What do the different settings on the ammeter terminal represent?

The different settings on the ammeter terminal represent different current measurement limits: 5A, 1A, 100mA, and 100µA.

How do you calculate the measured current using the ammeter?

To calculate the measured current, you use the formula N = (SD × SM) / BU, where N is the measured current, SD is the scale reading, SM is the maximum scale value, and BU is the selected range for the ammeter.

What are the key components of the voltmeter setting?

In the voltmeter setting, the key components include selecting the correct voltage range (e.g., 50V, 10V, 1V, 100mV) and connecting the terminals correctly: the positive terminal to the higher potential and the negative terminal to the lower potential.

How do you use the basic meter to measure the voltage of a lamp?

To measure the voltage of a lamp, you connect the voltmeter in parallel with the lamp, ensuring that the positive terminal of the meter is connected to the positive side of the lamp circuit and the negative terminal to the negative side.

What is the procedure for measuring current with the basic meter?

To measure current, you switch the function selector to ammeter, choose the appropriate current range (e.g., 1A), and connect the ammeter in series with the circuit. This allows the meter to measure the flow of current.

Why is it important to use the proper scale when measuring current with the ammeter?

Using the proper scale ensures accurate measurements. If the meter is set to an inappropriate range, the readings may be incorrect or the meter could be damaged due to exceeding its capacity.

What is the formula for calculating the measured voltage using the voltmeter?

The formula for calculating the measured voltage is similar to that of current: N = (SD × SM) / BU, where N is the measured voltage, SD is the scale reading, SM is the maximum voltage scale, and BU is the selected voltage range.

How do you interpret the needle reading on the basic meter?

To interpret the needle reading, you identify the scale the needle points to and use the scale’s maximum value to calculate the actual measured value. For example, if the needle points to 40 on a scale with a maximum of 100, you multiply the value accordingly to get the final reading.