The forward resistance of the diode cannot be measured with the ohm range of the digital multimeterThe forward resistance of the diode cannot be measured with the ohm range of the digital multimeter
digital multimeter
The digital multimeter is a multifunctional electronic component measuring instrument. Its general functions include measuring electricity and current (AC or DC), measuring voltage (AC or DC), and measuring capacitance, diodes, transistors and other electronic components. And according to different electronic components, you can also choose
Choose from different ranges and gears
How to use a digital multimeter
First of all, select the appropriate column for the meter pen according to the specific use. Digital multimeters generally have COM files. This gear has a ground symbol. Generally used to connect black test leads: In addition, there are three gears (used to measure voltage/resistance), rnA gear (used to measure small current), and A column (used to measure larger current). It is generally used to connect the red test lead, and there are special cases where it is not necessary to connect the test lead. For example, when measuring capacitance or a three-level tube, you only need to insert the component into the corresponding jack. Clockwise from 12 o'clock on the circumference, there are DC voltage gears, AC voltage gears, AC current gears, DC current gears, capacitor gears, diode gears, electric gears, and triode gears. Just select the specific situation. Pay attention to choose the appropriate range according to the measured component. Finally, the reading of the measured value of the digital multimeter does not need to consider the estimated reading. What value is displayed and what value needs to be noted on the gear position is not a multiple. , but the process, but the unit has a specific gear decision
The principle of the digital multimeter used to measure the resistance element is based on the Ohm's law of the closed circuit. The electromotive force in the formula is the voltage of the battery in the multimeter. The electric current in the circuit includes the measured resistance that needs to be tested. The adjustable resistance has different characteristics Internal resistance), and the constant resistance inside the multimeter, the current is calculated when the measured resistance is 0 ohms. According to Ohm's law in a closed circuit, the following formula can be obtained. 1=U/(Rg+ R fixed + R adjustment + R measurement) where U is the voltage of its internal battery, Rg is the resistance of the meter head, R is a fixed-value resistor connected in series with the meter head, and R adjustment is a good value The variable resistance, R measurement is the resistance to be measured. Due to the different ranges of the resistance to be measured, the fixed value resistance used is also different, which makes the multimeter divided into several levels.
When measuring with a multimeter, the resistance reading is actually the current reading, but the R measurement: 0 time rate current: 1=U/(Rg+ R adjustment + R adjustment + R measurement) is marked as R=0, when there is no current, the resistance is marked In the unimpeded large I and is a functional relationship, they are not a simple proportional relationship, choose different resistors and R must be different, when R = 0, 1 is different.
digital multimeter
The digital multimeter is a multifunctional electronic component measuring instrument. Its general functions include measuring electricity and current (AC or DC), measuring voltage (AC or DC), and measuring capacitance, diodes, transistors and other electronic components. And according to different electronic components, you can also choose
Choose from different ranges and gears
How to use a digital multimeter
First of all, select the appropriate column for the meter pen according to the specific use. Digital multimeters generally have COM files. This gear has a ground symbol. Generally used to connect black test leads: In addition, there are three gears (used to measure voltage/resistance), rnA gear (used to measure small current), and A column (used to measure larger current). It is generally used to connect the red test lead, and there are special cases where it is not necessary to connect the test lead. For example, when measuring capacitance or a three-level tube, you only need to insert the component into the corresponding jack. Clockwise from 12 o'clock on the circumference, there are DC voltage gears, AC voltage gears, AC current gears, DC current gears, capacitor gears, diode gears, electric gears, and triode gears. Just select the specific situation. Pay attention to choose the appropriate range according to the measured component. Finally, the reading of the measured value of the digital multimeter does not need to consider the estimated reading. What value is displayed and what value needs to be noted on the gear position is not a multiple. , but the process, but the unit has a specific gear decision
The principle of the digital multimeter used to measure the resistance element is based on the Ohm's law of the closed circuit. The electromotive force in the formula is the voltage of the battery in the multimeter. The electric current in the circuit includes the measured resistance that needs to be tested. The adjustable resistance has different characteristics Internal resistance), and the constant resistance inside the multimeter, the current is calculated when the measured resistance is 0 ohms. According to Ohm's law in a closed circuit, the following formula can be obtained. 1=U/(Rg+ R fixed + R adjustment + R measurement) where U is the voltage of its internal battery, Rg is the resistance of the meter head, R is a fixed-value resistor connected in series with the meter head, and R adjustment is a good value The variable resistance, R measurement is the resistance to be measured. Due to the different ranges of the resistance to be measured, the fixed value resistance used is also different, which makes the multimeter divided into several levels.
When measuring with a multimeter, the resistance reading is actually the current reading, but the R measurement: 0 time rate current: 1=U/(Rg+ R adjustment + R adjustment + R measurement) is marked as R=0, when there is no current, the resistance is marked In the unimpeded large I and is a functional relationship, they are not a simple proportional relationship, choose different resistors and R must be different, when R = 0, 1 is different.
