What are the advantages of the internal resistance of a digital multimeter compared to an analog mul

The internal resistance of digital multimeters is relatively large, and the readings are also very accurate.

The multimeter, referred to as the multimeter, is a multi-functional, multi-range, and easy-to-carry electronic meter. It can be used to measure physical quantities such as DC current, voltage, AC current, voltage, resistance, audio level, and transistor DC amplification. The multimeter consists of a meter head, a measuring circuit, a transfer switch and a test pen.

The basic principle of the multimeter is to use a sensitive magnetoelectric DC ammeter (micro-ampere meter) as the meter head. When a tiny current is passed through the meter head, there is a current indication. However, the meter head cannot pass a large current, so it is necessary to shunt or step down the voltage by connecting some resistors in parallel with series on the meter to measure the current, voltage and resistance in the circuit.

They are described below.

The principle of measuring DC current.

By connecting an appropriate resistor (called a shunt resistor) in parallel on the meter to divide the current, the current range can be extended. By changing the resistance of the shunt resistor, the current measurement range can be changed.

The principle of measuring DC voltage.

By connecting an appropriate resistor (called a multiplier resistor) in series on the meter to step down the voltage, the voltage range can be extended. By changing the resistance of the multiplier resistor, the measurement range of the voltage can be changed.

A digital multimeter is compared to an analog multimeter.

The internal resistance of the analog multimeter in use is generally small. Basically, it's 10-20 kohm V

For digital multimeters, the internal resistance when using is relatively large. And the readings are also very accurate.

Choose the right range. Short the two watch rods and calibrate them to zero. The two meter rods are in contact with both ends of the resistance of the tested electric sales, and the resistance value is read after the pointer is stable.

When measuring the resistance, after selecting the appropriate magnification gear, the two table pens in the middle of the bird line touch so that the pointer points at the zero position, if the pointer deviates from the zero position, the zero knob should be adjusted to make the pointer to zero, in order to ensure that the measurement results are accurate.

The unit of each gear is the same as the unit of the tick mark number, such as the gear is *10, *100, when the tick mark number is 10, the resistance value is 10*10=100 ohms, 10*100=1000 ohms, and so on.

Multimeter. It is divided into a multimeter and a pointer multimeter, which is an indispensable measuring instrument for power electronics and other departments. Generally, the main purpose is to measure voltage, current, and resistance.

It is a versatile, multi-range measuring instrument. Both digital and traditional play an important role in measurement, but what are the advantages and disadvantages of both? An analogue multimeter, an analogue multimeter is an average meter with intuitive and vivid readings.

There is generally no amplifier inside the analog multimeter, so the internal resistance is small. The frequency characteristics of an analog multimeter are non-uniform because of its low internal resistance and the use of many discrete components to form a shunt and voltage divider circuit. The internal structure of the orange spring pointer multimeter is simple, the cost is low, the function is less, the maintenance is simple, and the overcurrent and overvoltage capacity is strong.

The high output voltage and current of the analog multimeter make it easy to test thyristors and light-emitting diodes.

A digital multimeter is an instantaneous sampling instrument that takes a sample per second to display the measurement results, so reading the results is not as convenient as the analogue type of rubber liquid. The internal op amp circuit of a digital multimeter can make its internal resistance very large, which makes it less affected by the circuit under test and more accurate to measure. A digital multimeter has a lot of functions because it uses various circuits such as oscillation amplification, frequency division, protection, etc.

Because the internal structure of the digital multimeter adopts integrated circuits.

The overload capacity is poor, and it is generally not easy to repair after damage. The internal resistance of the dmm can be made very large, usually at 1 ohm or more. This results in less impact on the circuit under test and higher measurement accuracy.

Because the internal structure is a multi-purpose integrated circuit, the overload capacity is poor, and it is generally difficult to repair it after damage. The output voltage of DMM is low, which is not convenient for testing some components with special voltage characteristics. An analogue multimeter is an average meter with intuitive and vivid readings.

In general, the reading value is closely related to the swing angle of the pointer and is very intuitive. The frequency characteristics of an analogue multimeter are not uniform, whereas the frequency characteristics of an analogue multimeter are comparatively better because it has a smaller internal resistance and uses many discrete components to form a shunt and voltage divider circuit. A digital multimeter is an instantaneous sampling instrument.

The display of measurement results requires sampling per second. Sometimes the sampling results are just very similar, but not identical. Illustrate how to use a multimeter for example, not as easy to read as a pointer for reading results.

Due to the internal op amp circuitry, the internal resistance of a DMM can be very large, typically 1 mohm or more. This results in less impact on the circuit under test and higher measurement accuracy. DMM uses a variety of circuits such as oscillation, amplification, and crossover protection, so it has a wide range of functions.

For example, it can measure temperature, frequency, capacitance, and inductance, and act as a signal generator.

Due to the use of integrated circuits in the internal structure of digital multimeters, the overload capacity is poor, and it is generally not easy to repair after damage. The output voltage of the digital multimeter is low. For some components with special voltage characteristics.

The advantage is that it is very convenient and intuitive, but the disadvantage is that it is more complicated to operate, and it is more time-consuming to make.

It is easy to learn mathematics without potato ants, and these multimeters can be used in the knowledge of mathematics, which can be very simple to understand mathematical knowledge, and can clearly observe the knowledge of all aspects of mathematics, which can be a good link to the dust core.

The advantage is that the accuracy of the infiltration sail is very high, and its resolution is also very strong, it looks very intuitive, it is also very power-saving, it is very easy to carry, but it is not easy to repair after damage, and it is also very expensive, its overload capacity is not particularly good, and the output voltage is very low.

The digital multimeter sail belt has a particularly strong resolution, and the accuracy is very high, and the measurement speed is also very fast and intuitive, but the voltage output of the digital multimeter is particularly low, so it is not allowed to test some components with special voltage characteristics.

First of all, the accuracy is relatively high, and the resolution is also very strong, and the test function of the phase core spine is also very perfect, and the speed of measurement is also very fast, and Xiangburn is also relatively power-saving, and it is also very easy to carry, but the disadvantage is that there is no way to easily recover after damage.

The accuracy of this kind of watch is very high, and the resolution is also very strong, and the function is also perfect, but the power consumption of this hand-shouted watch is very large, and it is also very difficult to recognize.

1. The digital multimeter is an instantaneous style meter. It uses a sample once a second to display the measurement results, and sometimes the results of each sampling are only ten minutes close to the limbs, not exactly the same, which is not as convenient for reading the results as the pointer type.

2. Due to the internal op amp circuit of the digital multimeter, the internal resistance can be very large, often in 1m ohm or larger. (i.e., higher sensitivity can be obtained). This allows for less impact on the circuit under test and higher measurement accuracy.

3. The digital multimeter adopts a variety of oscillation, amplification, frequency division protection and other circuits, so it has more functions. For example, it can measure temperature, frequency (in a lower range), capacitance, inductance, signal generator, etc.

4. The digital multimeter has poor overload capacity due to the internal structure of multi-purpose integrated circuits, (but now some of them can automatically shift, automatic protection, etc., but the use is more complicated), and it is generally not easy to repair after damage.

5. The output voltage of the digital multimeter is low (usually not more than 1 volt). It is inconvenient to test some components with special voltage characteristics (such as thyristors, light-emitting diodes, etc.).

When using a multimeter, it is necessary to develop the habit of dialing the corresponding gear first when you do not pick up the watch pen, otherwise, once you dial the wrong one, it is easy to "burn" the multimeter.

After dialing to the corresponding gear, when measuring the resistance of the resistance without knowing the value, the gear starts from the middle, in order to make the reading more accurate, and then decides to adjust it to a higher or smaller level according to the reading; When measuring AC and DC current, the gear must be reduced from the high to the low gear, and when the gear is reduced, it is best to leave the measured place and lose silver, adjust the gear and then put on the pen.

Safety is the first auspicious posture, especially when measuring high voltage, do not touch the metal part of the watch pen.

The multimeter is one of the most basic measurement tools in the field of electronics, the use of the method is similar, relatively simple, it is recommended to find a master with a belt, half an hour to master the basic measurement method, so that the efficiency is the highest, and basically free Jiaohuai Zen flow learning.

If it is a digital multimeter without protection, you must confirm the position of the jack and the position of the function switch before measuring, especially if you can't measure the voltage in the current jack, it will definitely burn the meter.

Before using the Huai Sui digital multimeter, first confirm that the gear is correct. The measured resistance is measured in parallel. The measured current is measured in series, and if you want to make it simpler, you can use a smart digital multimeter, which will automatically recognize and change the difference.

The most important thing is to pay attention to the measurement, and the gear must not be selected wrong, which is also the most critical.

The main thing is to choose the appropriate gear before measuring, otherwise it is easy to damage the multimeter.

The two gauge rods are touched at both ends of the measured resistance, and the resistance value is read after the pointer is stable. When measuring the resistance, after selecting the appropriate magnification level, the two watch pens touch so that the pointer points to the zero position, if the pointer deviates from the zero position, the zero knob should be adjusted to make the pointer zero, so as to ensure the accuracy of the measurement results.

Before the test, first place the multimeter in a horizontal state, and depending on whether its watch hand is at the zero point (refers to the zero point of the current and voltage scale), if not, the mechanical zero adjustment below the meter head should be adjusted so that the pointer points to the zero point. According to the measured item, correctly select the measurement item and range switch on the multimeter.

If the order of magnitude to be measured is known, the corresponding magnitude range is chosen. If you do not know the magnitude of the value to be measured, you should start the measurement by selecting the maximum range, and then reduce the range when the pointer deflection angle is too small to read accurately. Generally, the deflection angle of the pointer is not less than 30% of the maximum scale as a reasonable range.

1. Voltage test. a.AC voltage test, first dial the meter to the test AC file (red circle in the figure), test, if you don't know what the voltage is, first dial the meter to the highest voltage level for testing, observe what the approximate voltage is, and then dial it to the nearest gear greater than the test voltage measurement, so that the measurement is more accurate.

b.Direct current measurements. Dial the meter to the DC measurement setting (circled in yellow).

The measurement method is the same as the measurement of alternating current, except that when measuring, the positive pole (red watch pen) of the multimeter touches the positive pole of the power supply to be measured, and the negative pole is connected to the negative pole.

2. Current test. Test the current and set the meter to the white circle as shown in the picture. First of all, the positive and negative poles of the meter pen are connected in series in the circuit, the positive pole of the meter pen is connected to the positive pole of the power supply, and the negative pole is connected to the positive pole of the electrical appliance, and the meter is dialed to the maximum range of the measured current for trial testing, and the measurement value of the meter needle is observed, and then the data is greater than the data at the time of the test, and the nearest range gear is measured.

Note! When measuring current, do not connect the meter pen directly to the positive and negative poles of the power supply, otherwise the multimeter will be burned!

3. Measurement of resistance. If you don't know how big the measured resistance value is, first dial the meter to the RXK file for testing, and observe the watch needle at this time: A

If the swing angle of the watch hand is very small (e.g. fretting), then dial the watch to the RX100 to measure, if the swing angle is still small, then to the RX10...And so on. b.If the hand swings at a wide angle to zero, then the watch is measured in the RX10K setting.

The basic requirement is that the measuring range is larger than the actual measured value, ideally the pointer pointing to the center of the dial during the actual measurement.

I didn't learn the things in the books, but the actual ones were from big to small.

Well, okay, you wait a minute, help you with the information.

How about resistance, test.

How to use the resistor of the analog multimeter: select the appropriate range. Short the two watch rods and calibrate them to zero.

The two gauge rods are touched at both ends of the measured resistance, and the resistance value is read after the pointer is stable. When measuring the resistance, after selecting the appropriate magnification file, the two table pens touch Doubi to make the pointer point at the zero position, if the pointer deviates from the zero position, the zero knob should be adjusted to make the pointer zero, and the sock pin stove ensures the accuracy of the measurement results.

Before the test, first place the multimeter in a horizontal state, and depending on whether its watch hand is at the zero point (refers to the zero point of the current, the voltage scale), if not, the mechanical zero adjustment below the meter head should be adjusted, so that the pointer points to the zero point. According to the measured item, correctly select the measurement item and range switch on the multimeter. If the order of magnitude to be measured is known, the magnitude range corresponding to the cavity of the phase is selected.

If you do not know the order of magnitude of the pure measured value, you should start the measurement by selecting the maximum range, and then reduce the range when the pointer deflection angle is too small to read accurately. Generally, the deflection angle of the pointer is not less than 30% of the maximum scale as a reasonable range.

What is 200?

Classmate, do you have the complete question?

The number table directly reads the number of cavities, such as: 2k files show Li Shanying representatives, representative files display representatives, representative files display or representatives.