What do the numeric numbers on the multimeter mean? How are resistances, voltages, etc. measured?

The symbol for the resistance file on the DMM is "".

In the resistance gear, k represents that gear is k, i.e., kiloohms. m stands for m, i.e., megaohms. The K and M of the DMM resistor file should be uppercase K and M, note that the lowercase M and uppercase M are marked here to represent different meanings.

If it is lowercase, m represents milliohms, while uppercase m represents megaohms.

Measurement accuracy: Accuracy refers to the maximum allowable error in a specific use environment. In other words, accuracy is used to indicate how close the measured value of the DMM is to the actual value of the signal being measured.

For numeric multimeters, accuracy is usually expressed as a percentage of the reading. For example, a reading accuracy of 1% means that the actual voltage may be in between when the display of a digital multimeter is.

In the detailed specification, there may be specific values added to the basic accuracy. What it means is the number of words to be added to transform the rightmost part of the display. In the previous example, the precision might be marked as (1%+2).

Therefore, if the GMM reading is, the actual voltage will be in between.

The accuracy of the analog meter is calculated as an error over the full scale, not as a reading displayed. The typical accuracy of an analog table is 2% or 3% of the full scale. The typical basic accuracy of a digital multimeter is between ( and (, or even higher) of a reading.

Learning how to use a multimeter is a compulsory course for every enthusiast (beginners are recommended to master the analog multimeter first). Let's talk about how to use the pointer multimeter correctly, the pointer multimeter is shown in the figure

The pointer multimeter is widely used, and the measurement items, types, etc., are more numerous, and the measurement is also more intuitive, which is deeply loved by enthusiasts. Let's talk about several issues that should be paid attention to before measurement and how to measure current, voltage, and resistance

1. First of all, see if the multimeter needle is in the zero position, otherwise it needs to be mechanically zeroed.

2. Whether the two watch pen wires are connected correctly (the red watch pen is inserted into the positive pole, and the black watch pen is inserted into the negative pole), and the multimeter should be placed flat.

3. It is very important to have a clear measurement target and set the meter to the correct measurement gear! Especially when measuring voltage, the meter must not be set to the measurement current level, otherwise it will burn!

4. When measuring the voltage, the meter should be dialed to the nearest and greater than the measured voltage level, if the measured voltage is unknown, the meter should be dialed to the highest voltage for trial once, and then according to the measured voltage. When measuring the DC voltage, the red pen touches the positive pole to be measured, and the black pen touches the negative pole.

5. When measuring the resistance, the short-circuit of the meter pen should be adjusted to zero every time the measurement gear is converted.

6. When measuring the current, connect the meter in series in the circuit, the red watch pen contacts the positive pole of the power supply, and the black watch pen contacts the positive pole of the electrical appliance, do not exceed the range of the measured current, otherwise, the meter needle is easy to be broken, etc., and the meter head will be damaged.

7. The position of the table should be far away from the magnet to avoid the increase of measurement error.

8. Before using the multimeter, beginners must carefully read the instruction manual (this is very important, the measurement method of any pointer multimeter is the same), see how to measure the current, voltage, resistance, that is, the operation method, how to choose the multimeter function knob. Due to the large length of the article, I will not repeat it here.

Mechanical multimeter (also known as universal meter), when measuring current, voltage, resistance, must distinguish the gear:

1.When measuring the current, the second row of the meter reading, the gear arrow should be dialed to the current gear, and the current size should be roughly estimated, which is generally divided into three gears within 20 amperes, 500 ampere gears and microampere level, of which the 20 ampere gear should be changed to the meter pen socket position;

2.When measuring the voltage, the meter reads the first.

In the second and third rows, the gear arrow is dialed to the voltage gear, and it should be noted that there are two gear areas of AC voltage and DC voltage.

3.When measuring the resistance, the first row of the reading on the table, the gear arrow is dialed to the ohm range, and the measurement gear is x1, x10, x100, x1k, x10k, and the measured result is the result calculated by the number on the table and the gear in the direction of the arrow.

There are two display methods of multimeter, one is pointer, now the most used is the liquid crystal digital display, no matter what kind of measurement current and voltage should first distinguish whether it is alternating current or direct current, AC should choose AC current or voltage gear, DC should choose DC current or voltage gear, and the range should be larger than the actual one, so as not to damage the multimeter. To measure the resistance, you should choose the resistance gear, but also to estimate the maximum value first, and then choose a higher range gear, the resistance value exceeds the range of the digital meter shows 1. There is also a kind of digital meter that automatically selects the range, this kind of meter does not need to select the gear, and it will be automatically selected after receiving the circuit, which is very convenient.

I don't know what kind of multimeter you use, there is a pointer type, digital, digital multimeter is divided into semi-automatic and fully automatic, semi-automatic and pointer type need the same principle gear measurement, fully automatic multimeter, such as measuring resistance, diode, DC voltage, AC voltage, can be without shifting, hardware self-identification, the number on the display screen plus the unit behind is the measured value, if it is semi-automatic, you must choose the range you want to adapt according to the size of your estimated value, if you are not sure, First choose the maximum range, **, and then choose a similar range, the same is true for the pointer meter, voltage resistance, do not need to replace the jack of the meter, only the current gear needs to replace the jack.

This situation depends on the need to choose the corresponding gear, if you don't understand well, you can take a closer look at the use of the multimeter or ask someone who understands.

Selecting different ranges will show different resistance values, and the resistance value to be measured should be smaller than and closest to the selected range is more accurate.

A digital multimeter, a multi-purpose electronic measuring instrument, generally contains functions such as ampere meter, voltmeter, ohmmeter, etc., and is sometimes called a multimeter, multimeter, multimeter, or triple meter.

DMMs are suitable for portable devices for basic fault diagnosis, as well as devices placed on a workbench with a resolution that can be achieved.

Seventh, eighth. Resolution is the way to judge the quality of a table's measurement results. Knowing the resolution of a table allows you to know if you can see small changes in the signal being measured.

For example, if the resolution of a digital multimeter in the 4V range is 1mV, then when measuring a 1V signal, you can see a small change of 1mV (1 1000 volts).

If you're going to measure a length of less than 1 4 inches (or 1 millimeter), you certainly won't use a ruler with the smallest unit of inches (or centimeters). If the temperature is, then it is useless to measure with a thermometer with only integer markers. You need a thermometer with a resolution.

The number of digits and words are used to describe the resolution of the table. Multi-purpose tables are categorized by the number of digits and words they can display.

A 3-and-a-half-digit table can display three digits from 0 to 9, and one half-digit (with only 1 or no digits). A three-and-a-half-digit digital table can achieve a resolution of 1999 words. A four-and-a-half-digit digital table can reach a resolution of 19,999 words.

The resolution of describing a table of numbers in words is better than describing it in bits, and the resolution of a table of 3 and a half digits has been increased to 3200 or 4000 words.

The 3200-word digital table provides better resolution for some measurements. For example, a 1999-word table is unlikely to show up when measuring voltages greater than 200V. The 3200-word digital meter can still be displayed when measuring a voltage of 320 volts.

When the measured voltage is higher than 320V, and the resolution to be achieved, it is necessary to use the most expensive 20,000-word digital table.

<>2. Find the resistance area, see that there are 200 ohms to 2m ohms, select the gear according to the size of the resistance value when measuring, if you don't know the size of the resistance value from large to small, short the red and black watch pen before testing, calibration.

3. If you want to measure the resistance of 0-2k ohms, adjust the gear to 2k ohms.

4. For example, the resistance value on the test board is listed, first hit the gear in the resistance area, and then connect the meter pen to both ends of the resistance.

5. It is best to remove the resistance and measure.

6. The resistance value of the last reading can be done.

The reading in the chart is 2 euro points 299

The level of the resistor indicates the maximum range of the multimeter, for example, the 200 ohm range can measure the resistance within 200 ohms, and the 2k ohm can measure the maximum resistance of 2k ohms, and the same goes for the future. Reading: The value of the 200 ohm gear is directly from the screen reading limit, the unit is ohm, 2k, the reading of these three gears is also read from the screen, the unit is k ohm, the reason why the three k ohm gears are set, the main reason is that the measurement accuracy of these three gears is different, and the same is true for the m ohm level.

If I am resistive 200 ohms, how do I read the reading?? Europe.

2k ohms, the reading is. How do you read 002? 2 euros.

20k ohms, how to read the reading?? 250 euros.

If you have 200k euros, how do you read the reading?? 200 euros.

At 2 m ohms, the reading is. How do you read 002? 2,000,000 euros.

How do you read the reading at 20 m ohms??? 20000000 euros.

Methods and precautions in the use of digital multimeters Due to the advantages of accurate measurement, convenient value and complete functions, digital multimeters that are popular with radio enthusiasts generally have resistance measurement, on-off sound detection, and diode forward conduction voltage measurement. AC and DC voltage and current measurement, transistor amplification and performance measurement, etc. Some digital multimeters have added functions such as capacitance capacity measurement, frequency measurement, temperature measurement, data memory and voice reporting, which bring great convenience to the actual detection work.

However, due to improper use, the digital square meter is easy to cause damage and failure of the components in the table during the actual detection. The digital multimeter is recommended to choose Beijing Fanshi measurement and control technology, which is currently engaged in electronic measuring instruments, high-frequency communication instruments, testing instruments, measurement and calibration instruments of the franchise company. With the support of all walks of life and the efforts of all employees, we have established a high reputation and credibility in the field of instrument sales, and now have a perfect market system, marketing management system and customer service system.