How to measure 4~20mA sensor with multimeter
There are two measuring methods:
1. Pass the current range test of multimeter, and the steps are as follows:
The red probe of multimeter is connected to the hole of mA, and the black probe is connected to COM.
Adjust the multimeter to DC mA.
The red probe of multimeter is connected to the positive pole of 4-20mA sensor output, and the black probe is connected to the negative pole of 4-20mA sensor output.
Read the indicator from the display area of the multimeter, and the read indicator is the current value.
2. Through the multimeter's 10,000-voltage measurement, for the multimeter without current test function, the current value can be measured by voltage, as follows:
At the output of 4-20mA sensor, a sampling resistor of about 100 ohms is connected.
The red probe of multimeter is connected to the hole of mA, and the black probe is connected to COM.
Adjust the gear of multimeter to DC V gear.
The red probe of multimeter is connected to the positive pole of 4-20mA sensor output, and the black probe is connected to the negative pole of 4-20mA sensor output.
Read the indicator from the display area of the multimeter. The read indicator is the voltage value. Divide the read indicator by the resistance value (for example, 100 ohms) to get the current value.
Use the direct current function of multimeter, 20mA gear (if not, choose 100mA gear), and 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: the red stylus is connected to the green wire, and the black stylus is connected to the yellow wire.
