How a multimeter measures current, voltage and resistance
A multimeter is a multi-function measuring meter, which can measure current and voltage, as well as other values such as resistance, but the method of use is more complicated. So, how to use the multimeter, the following will introduce to you.
How to use the multimeter:
1. Voltage measurement:
1. Measurement of DC voltage: First, insert the black test lead into the [com] hole, and the red test lead into the [VΩ];
2. Select the knob on the multimeter to a range larger than the estimated value (note: the values on the dial are the maximum range, [V-] means DC voltage range, [V～] means AC voltage range, [A] is current gear), then connect the test leads to the power supply or both ends of the battery;
3. Keep the contact stable. The value can be read directly from the display screen. If it is displayed as [1], it means that the range is too small, then the range should be increased before measuring the industrial electrical appliance. If [-] appears on the left side of the value, it means that the polarity of the test lead is opposite to that of the actual power supply, and the red test lead is connected to the negative pole;
4. AC voltage measurement: The test pen jack is the same as the DC voltage measurement, but the knob should be turned to the desired range at the AC gear [V~]. There is no positive or negative AC voltage, and the measurement method is the same as the previous one. Whether measuring AC or DC voltage, pay attention to personal safety and do not touch the metal part of the test pen with your hands;
Second, the current measurement:
1. Measurement of DC current. Insert the black test lead into the [com] hole first. If measuring the current greater than 200mA, insert the red test lead into the [10A] jack and turn the knob to the DC [10A] level; if measuring the current less than 200mA, insert the red test lead into the [200mA] jack, turn the knob on to a suitable range within 200mA of DC. Once adjusted, you can measure. String the multimeter into the circuit, keep it stable, and you can read it. If it is displayed as [1], then the range should be increased; if - appears on the left side of the value, it means that the current flows into the multimeter from the black test lead;
2. AC current measurement: The measurement method is the same as 1, but the gear should be set to the AC gear, and the red pen should be inserted back into the [VΩ] hole after the current measurement is completed;
Third, the measurement of resistance:
Insert the test leads into the [com] and [VΩ] holes, turn the knob to the desired range in [Ω], and connect the test leads to both ends of the resistor. You can touch the resistance with one hand during measurement, but do not put the two Touch both ends of the resistor with one hand at the same time, which will affect the measurement accuracy. When reading, keep the test leads and the resistance in good contact; note: the unit is [Ω] in the [200] range, the unit is [KΩ] in the [2K] to [200K] range, and the unit above [2M] is 【MΩ】;
The above is the answer to the use of the multimeter, I hope it can help you
