There are two measurement methods:
1. Pass the current test of the multimeter, the steps are as follows:
The red test lead of the multimeter is connected to the hole of mA, and the black test lead is connected to COM.
Adjust the gear of the multimeter to the DC mA gear.
The red test lead of the multimeter is connected to the positive pole of the 4-20mA sensor output, and the black test lead is connected to the negative pole of the 4-20mA sensor output.
Read the reading from the display area of the multimeter, and the reading is the current value.
2. Through the multimeter's 10,000-voltage range measurement, for the multimeter without the current test function, the current value can be measured by the voltage, and the steps are as follows:
At the output of the 4-20mA sensor, connect a sampling resistor of about 100 ohms.
The red test lead of the multimeter is connected to the hole of mA, and the black test lead is connected to COM.
Adjust the gear of the multimeter to DC V gear.
The red test lead of the multimeter is connected to the positive pole of the 4-20mA sensor output, and the black test lead is connected to the negative pole of the 4-20mA sensor output.
Read the reading from the display area of the multimeter. The reading is the voltage value. Divide the reading by the resistance value (such as 100 ohms) to get the current value.
Use the DC current function of the multimeter, 20mA gear (if not, choose 100mA gear), and you can directly test the sensor output. If it is a desktop digital multimeter, you can also use any sensor function to let the instrument directly test the physical quantity sensed by your sensor. Wiring method: connect the red test lead to the green wire, and the black test lead to the yellow wire
