Illustration of how to use the 500 analog multimeter

The multimeter is one of the main instruments used by circuit board maintenance personnel, industrial equipment maintenance personnel, maintenance personnel, and household appliance maintenance personnel to check and judge faults. It can be said like this: "No matter it is any equipment or machine with circuits in all walks of life, it must be maintained away from home. Don’t turn on the multimeter! "In order to let more friends know how to use the multimeter, the editor of Xiwang specially compiled the method of using the multimeter and how to use the pointer multimeter for friends who are engaged in equipment repair, equipment maintenance, and other professions to share.

The real name of a multimeter is a three-purpose meter. Because it can measure three electrical parameters: voltage, current, and resistance, the manufacturer calls it a three-purpose meter. And because the multimeter can be used in many electrical maintenance situations, people also call it a three-purpose meter. It is customary to call it a multimeter, indicating its wide application. This article takes the widely used 500 analog multimeter as an example to explain its use in detail.

How to use a multimeter to measure resistance

When repairing electrical circuits, when we determine that there is a fault in a certain part of the circuit and want to accurately determine whether it is caused by wire breakage or component damage, using the resistance range of the 500-type pointer multimeter can help the maintenance personnel determine the specific fault. element. The specific method of measuring resistance is as follows:

Calibrate the multimeter before measuring resistance. Please refer to Figure 1. The method is to first turn the No. 1 knob of the multimeter to the ω ohm position, see the label of the knob in the picture, then turn the No. 3 knob to select the appropriate measurement range, and then short-circuit the two test leads of the multimeter. Turn the No. 2 knob shown in the figure to adjust the pointer of the multimeter to the zero position. After zeroing the 500 pointer multimeter, you can start measuring resistance.

Tips: Zero adjustment is very important. If zero adjustment is not performed before measuring resistance, the measured resistance value will be inaccurate. During zero adjustment, zero adjustment must be performed after changing different measuring ranges!

When measuring, you must first disconnect the part to be measured, and connect the two test leads to both ends of the component being measured. Be careful not to hold both ends of the component with both hands at the same time when measuring. It is best to use alligator clips to clamp the component. Measurements are made on both pins.

Reading the resistance measurement value: Multiply the measurement range number on knob 3 of the multimeter by the value indicated by the first pointer on the multimeter head, which is the value of the measured resistance. For example: to measure a resistor with a resistance of 51Ω, place the multimeter’s measuring knob No. 1 in the ω ohm position, and turn the multimeter’s measuring knob No. 3 to 10. Please refer to Figure 2.

At this time, the pointer of the multimeter points to the position of 5.5 (see the first grid in Figure 2), then the actual measured value of this resistor is 5.5×10=55ω. Others can be deduced by analogy. If you are using a 500 pointer multimeter to measure resistance,

How to use a multimeter to measure voltage

When repairing electrical circuits, using the AC voltage range or DC voltage range of the 500 pointer multimeter to measure the voltage of the relevant circuit can help maintenance personnel quickly determine the scope of the fault and improve maintenance efficiency. Please see Figure 3 for the specific measurement method of voltage:

When measuring voltage using the AC voltage range or DC voltage range of the 500 analog multimeter, you should now place the multimeter's No. 2 knob in position, and then place the No. 1 knob in the appropriate range. Note: When measuring DC voltage, select the DC range, and Pay attention to the polarity of the test leads when connecting. The positive pole is connected to the positive pole of the measured point, and the negative pole is connected to the negative pole of the measured point. To measure AC voltage, select the AC range. There is no polarity difference between the two test leads when measuring. Just connect the two test leads in parallel with the point to be measured, but you should pay attention to safety when measuring.

For the measurement value, please look at the second grid of the multimeter. Divide the scale line of the second grid into equal parts according to the measurement range. The value read directly is the measured voltage value. For example: In Figure 3, what is being measured is a 9v laminated battery. When measuring, turn knob 2 to the voltage position, turn knob 1 to the DC 50v range, and connect the red pen of the multimeter to the positive terminal of the battery. , the black test lead is connected to the negative terminal of the battery. At this time, the pointer on the multimeter head displays the measured voltage value of the battery. Please refer to Figure 3 for specific voltage values. In Figure 3, because the measurement range is 50v, the second grid is divided into 50 equal parts, so that the voltage value of each small grid is 1v. In the measurement result, the pointer points In the ninth cell, the voltage value of the measured battery is 9v. The calculation method of other voltage values

How to use a multimeter to measure current

When repairing electrical circuits, current settings are rarely used for testing. Detecting current requires connecting the test leads of a multimeter in series to the circuit, which is troublesome. Therefore, current settings are rarely used for testing in actual maintenance work. The specific detection methods are as follows:

Turn the multimeter's No. 1 knob to the current position, and the No. 2 knob to select the appropriate range according to the measured current value. If you do not know the current value of the line to be detected, you should gradually decrease from the large range to avoid The multimeter is damaged.

The reading of the current measurement value is also based on the second grid. Divide the second grid into equal parts according to different measurement values, and you can read the actual measured current value.

The use of the 500-type analog multimeter is not very complicated, but it is a little troublesome to read the measured values. It will be a bit unfamiliar when you first learn how to use the multimeter. As long as friends read and practice more, they will become familiar with reading the measured values. , you won’t feel strange anymore.