Digital multimeter voltage measurement red and black pen inserted in which two positions
1, AC and DC voltage measurement: according to the need to range switch to DCCV (DC) or ACV (AC) of the appropriate range, red pen inserted into the V / Ω hole, black pen inserted into the COM hole, and will be connected in parallel with the measured line pen, the reading is displayed.
2, AC and DC current measurement: the range switch to DCA (DC) or ACA (AC) of the appropriate range, the red pen inserted into the mA hole (<200mA) or 10A holes (>200mA), the black pen inserted into the COM hole, and will be connected in series in the measured circuit can be multimeter. When measuring direct flow, the digital multimeter can automatically display the polarity.
3, resistance measurement: the range switch to Ω of the appropriate range, the red pen into the V / Ω hole, the black pen into the COM hole. If the measured resistance value exceeds the maximum value of the selected range, the multimeter will display 1, then you should select a higher range.
When measuring resistance, the red pen is positive and the black pen is negative, which is the opposite of the pointer multimeter. Therefore, when measuring transistors, electrolytic capacitors and other components with polarity, you must pay attention to the polarity of the pen.
Digital multimeters are relatively simple measuring instruments. In this article, the author teaches you the proper use of digital multimeters. From the digital multimeter voltage, resistance, current, diode, transistor, MOS field effect tube measurement and other measurement methods, so that you can better master the multimeter measurement method.
Before use, you should read the relevant instruction manual carefully and familiarise yourself with the role of the power switch, range switch, jacks and special sockets. Place the ON/OFF switch in the ON position, check the 9V battery, if the battery voltage is insufficient, it will be shown on the display, then the battery needs to be replaced. If the display does not show, proceed as follows.
The symbol next to the test pen jack indicates that the input voltage or current should not exceed the indicated value, this is to protect the internal wiring from damage. Before testing. The function switch should be placed at the desired range.
