Before the electromagnetic flowmeter is ready to be used after installation, what inspection should be done?

The electromagnetic flowmeter is the same as the usual measuring instruments. Before the electromagnetic flowmeter is put into operation after installation and wiring, it is necessary to check whether the following installation and wiring are correct and whether the instrument can work normally. Before the electromagnetic flowmeter is put into operation, the sensor must be filled with the actual measuring medium, and after the power is turned on, the zero point is adjusted in a static state.

After the electromagnetic flowmeter is put into operation, check the zero point according to the medium and the conditions of use. Regularly check the zero point for the easy-to-precipitate, easily polluted electrodes, solid-containing non-clean media, etc. In the initial stage of operation, check more to obtain experience and determine the normal inspection cycle. .

Electromagnetic flowmeters For conditional users, several basic parameters of the sensor should be measured and recorded before the electromagnetic flowmeter is put into operation:

1 Insulation resistance of the electrode (in case of sensor empty tube, insulation resistance of the two resistors to the instrument case or ground);

2 Insulation resistance of the excitation coil (insulation resistance of the excitation coil to the instrument housing or ground);

3 The cold resistance value of the excitation coil (that is, the copper resistance value of the enameled wire of the excitation coil);

4-electrode contact resistance

The sensor is filled with liquid. Measure the resistance between the electrode and the ground. The contact resistance of the two electrodes should be approximately the same. These data are helpful in analyzing the cause of the failure of the electromagnetic flowmeter after a period of operation. For example, when the contact resistance of two electrodes changes, it indicates that the electrode is likely to be contaminated;

The contact resistance becomes larger, the contaminants may be insulating deposits; the contact resistance becomes smaller, the contaminants may be conductive deposits; the contact resistance of the two electrodes is asymmetric, indicating that the two electrodes are not contaminated to varying degrees The drop in the insulation resistance of the electrode and the excitation coil indicates the degree of moisture in the sensor; when the insulation resistance drops to a certain degree, it will affect the normal operation of the electromagnetic flowmeter. The cold resistance value of the excitation coil is a parameter that guarantees the normality of the excitation coil.

Electromagnetic Flowmeter