Introduction to Digital Multimeter Measurement Tips
Capacitor: also known as "capacitance", refers to the amount of charge stored at a given potential difference. Generally speaking, charges move under force in an electric field. When there is a medium between conductors, it hinders the movement of charges and causes them to accumulate on the conductors, resulting in the accumulation and storage of charges. The amount of stored charge is called capacitance. Capacitor refers to the ability to accommodate an electric field.
Some digital multimeters have the function of measuring capacitance, and the UT39C has a range of 20nF, 200nF, and 20 μ F. When measuring, the two pins of the discharged capacitor can be directly inserted into the Cx socket on the meter board, and the display data can be read after selecting the appropriate range.
(1) Set the function switch to the capacitor range.
(2) Insert the capacitor to be tested into the capacitor test input socket. If it exceeds the range and the LCD displays "1", the range needs to be increased.
(3) All capacitors must be fully discharged before testing.
6. Digital multimeter for measuring frequency and duty cycle
Frequency: refers to the number of times a periodic change is completed per unit of time, and is a quantity that describes the frequency of periodic motion.
Duty cycle: refers to the ratio of time that the effective level occupies within one cycle. The duty cycle of the square wave is 50%, and the duty cycle is 0.5, indicating that the positive level occupies 0.5 cycles.
(1) Turn the function selection switch to Hz%, taking UT195E as an example, as shown in the figure.
(2) Insert the red and black probes into the V Ω Hz and COM input terminals respectively.
(3) Connect the test end of the probe wire in parallel to the signal source under test.
(4) When conducting frequency measurement, press the SELECT key once to enter the duty cycle measurement state, and press the SELECT key again to return to the frequency measurement state.
(5) When measuring current or voltage, press the Hz/% key once to enter the frequency measurement state, press the Hz/% key again to enter the duty cycle measurement state, and press the Hz/% key for the third time to return to the original measurement state.
(6) Read the current measurement result from the display screen.
