How to judge the quality of electromagnetic flowmeter electrodes?

Case introduction

Methods to judge the quality of electromagnetic flowmeter electrodes include the following aspects:

Appearance inspection. Observe whether the appearance of the electromagnetic flowmeter is complete, whether the seal is good, whether the screen displays normally, etc. If there is damage to the appearance or abnormal display, it will need to be repaired or replaced.

Measure the contact resistance between the electrode and the liquid. Use a digital voltmeter to measure the resistance value of the electrode in contact with the liquid. The resistance value should be between 1 kilohm and 1 megohm, and the resistance values ​​of wire numbers "1" and "2" and "1" and "3" should be approximately symmetry.

Check the internal connectivity of the electrode. Check whether the contact point between the electrode and the cable is tight, whether the connection is stable, etc. If you find there is a problem with the contact between the electrode and the cable, you can try rewiring or replacing the cable.

Measure the resistance of the excitation coil. Measure the resistance value of the excitation coil to determine whether there is an inter-turn short circuit in the excitation coil. The resistance value should be between 30 ohms and 170 ohms.

Measure the insulation resistance of the excitation coil to ground. Measure the insulation resistance of the excitation coil to ground to determine whether the sensor is damp. The resistance value should be greater than 20 megohms.

Measure the electrode potential. Use a multimeter or special electrode testing instrument to quickly measure the potential of the electrode to determine whether it is qualified.

Check the electrode connector. Check whether the electrode connector is loose and the contact is good.

Observe the signal quality. Observe the signal quality of the electromagnetic flowmeter. If there are problems such as poor stability and large fluctuations, you need to check the electrodes and connecting signal lines.

Regular cleaning and maintenance. Clean and maintain the electrode regularly to ensure its normal use and prevent the inside of the electrode from being blocked by foreign matter.

Through these inspection methods, the quality of the electromagnetic flowmeter electrode can be effectively judged.