Which two holes are inserted into the multimeter's ammeter pens?
The pens of the multimeter are divided into red and black. The red pen should be inserted into the jack marked with "+" and the black pen into the jack marked with "-".
The main performance index of the multimeter basically depends on the performance of the meter head. The sensitivity of the head refers to the DC current value flowing through the head when the pointer of the head is deflected to full scale, the smaller this value is, the higher the sensitivity of the head is. The greater the internal resistance when measuring voltage, the better its performance.
1, the gear should be consistent with the type of current to be measured. That is, according to the AC and DC type of current you want to measure, choose the correct gear, AC corresponds to AC gear, DC corresponds to DC gear;
2, choose the appropriate range, otherwise, it is very likely to lead to burn the multimeter. If, do not know the size of the measured current, we must choose the maximum range. For example, the digital multimeter 20 ampere gear, you can measure the current of 4.4 kilowatts of electricity;
3, connect the multimeter in series to the firewire of the electrical appliance. To do this, the first step is to first disconnect the switch of the appliance. The second step is to unplug and connect the meter in series; the third step is to plug it in and close the switch. At this time, the multimeter reading both for the requested.
Note: high-power appliances with this method of measuring current is very dangerous, and easy to burn the meter. It is recommended to use a clamp-on ammeter. In this way, that is safe and easy to do.
Digital multimeter voltage measurement red and black pen inserted 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 holes, black pen inserted into the COM holes, and will be measured in parallel with the pen line, 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 meter pens.
