How to measure DC voltage with a digital multimeter

As a beginner, correct use is the most basic skill. With the development of technology, more and more electronic practitioners use digital multimeters. This article mainly explains how to use a digital multimeter to measure DC voltage.

1. Measurement method of DC voltage

1. Insert the black test lead into the com jack and the red test lead into the v/ω jack.

2. Place the function switch in the DC voltage range v-range, and connect the test leads to the test (measuring open circuit voltage) or load (measuring load voltage drop) to keep the contact stable. Values ​​can be read directly from the display and units confirmed.

3. If it displays "1.", it means that the measuring range is too small, so you need to increase the measuring range before measuring.

4. If "-" appears on the left side of the value, it means that the polarity of the test lead is opposite to the actual power supply polarity. At this time, the red test lead is connected to the negative pole.

When measuring, turn the switch to the required voltage level. When measuring, the test pen should be connected in parallel to the circuit under test. If you do not know the range of the voltage to be measured, you can first use a larger measurement limit to measure the approximate value, and then move to the corresponding measurement limit.

2. Operation tips

1. Select the DC voltage range. When you don’t know the voltage range, you should start from the maximum range.

2. Pay attention to the voltage polarity, that is, connect the red test lead to high potential and the black test lead to low potential.

3. The meter should be connected in parallel at both ends of the circuit under test.

3. Measurement steps of DC voltage

Step 1: Rotate the multimeter to the DC voltage range of 20v.

Step 2: Close s1 on the physical circuit.

Step 3: Test the voltage across the LED: 2.2v

Step 4: Test the voltage at both ends of the power supply: 6v

Step 5: Test the voltage across 360 ohms: 3.8v

Step 6: Test the voltage across 200 ohms: 4v

Step 7: Test the voltage across 100 ohms: 2v

4. Precautions

1. If the measured voltage range is not known, set the function switch to the maximum range and gradually decrease it.

2. If the display only displays "1.", it means that the range is too small, and the function switch should be set to a higher range.

3. "" means do not measure voltages higher than 1000v. It is possible to display higher voltage values, but there is a risk of damaging the internal circuits.

4. When measuring high voltage, pay special attention to avoid electric shock.

5. When selecting function and range, the test leads should leave the test point.