Which two holes should the multimeter measure ammeter pens be inserted into?
The test leads of the multimeter are divided into red and black. When in use, insert the red test lead into the jack marked "+", and insert the black test lead into the jack marked "-".
The main performance index of a multimeter basically depends on the performance of the meter head. The sensitivity of the meter head refers to the DC current value flowing through the meter head when the pointer of the meter head is deflected at full scale. The smaller the value, the higher the sensitivity of the meter head. The greater the internal resistance when measuring voltage, the better its performance.
1. The gear position should be consistent with the type of current to be measured. That is, according to the AC and DC type of the current you want to measure, select the correct gear, AC corresponds to AC gear, and DC corresponds to DC gear;
2. Select the appropriate range, otherwise, it is very likely to burn the multimeter. If you do not know the magnitude of the measured current, you must choose the maximum range. For example, a digital multimeter with a 20 ampere range can measure a current of 4.4 kilowatts;
3. Connect the multimeter in series to the live wire of the electrical appliance. To do this, the first step is to turn off the electrical switch. The second step is to unplug the plug and connect the meter in series; the third step is to plug in the plug and turn on the switch. At this time, the reading of the multimeter is as desired.
Note: It is very dangerous to use this method to measure the current of high-power electrical appliances, and it is easy to burn the meter. A clamp ammeter is recommended. In this way, it is safe and simple.
Where should the red and black pens of the digital multimeter be inserted?
1. Measurement of AC and DC voltage: Turn the range switch to the appropriate range of DCCV (DC) or ACV (AC) as required, insert the red test lead into the V/Ω hole, insert the black test lead into the COM hole, and connect the test lead to the circuit under test in parallel , the reading is displayed.
2. Measurement of AC and DC current: Turn the range switch to the appropriate range of DCA (DC) or ACA (AC), insert the red test lead into the mA hole (<200mA) or 10A hole (>200mA), and insert the black test lead into the COM hole , and connect the multimeter in series to the circuit under test. When measuring DC flow, the digital multimeter can automatically display the polarity.
3. Resistance measurement: Turn the range switch to the appropriate range of Ω, insert the red test lead into the V/Ω hole, and insert the black test lead into the COM hole. If the measured resistance value exceeds the maximum value of the selected range, the multimeter will display 1, and a higher range should be selected at this time.
When measuring resistance, the red test lead is positive and the black test lead is negative, which is just the opposite of the pointer multimeter. Therefore, when measuring polar components such as transistors and electrolytic capacitors, you must pay attention to the polarity of the test leads.
