Electromagnetic flowmeter often appear several kinds of failure

Case introduction

　　Electromagnetic flowmeter is the use of Ferrari magnetic induction principle designed flowmeter. Its advantages are corrosion resistance, and wear resistance, long service life, and secondly, it can carry out bidirectional measurement, convenient operation. Electromagnetic flowmeter is now used in metallurgy, industry, chemical industry, agricultural irrigation, environmental protection, medicine and other fields. Frequently encountered faults are:

　　1, debugging process failures, in the electromagnetic flowmeter began to install and debugging occurs, but once improved and eliminated, later generally will not reoccur under the same conditions. Common failures in the commissioning process mainly include improper installation, environmental interference and the impact of fluid properties.

　　Piping system and installation, etc.

　　Failure is caused by incorrect installation location of the electromagnetic flow sensor, such as the flow sensor is installed in the high point of the pipe network, where the trapped gas is prone to accumulate, electromagnetic flow meter flow sensor behind the back pressure is not available, the liquid is discharged directly into the atmosphere, in its measurement of the pipeline to form an incomplete pipeline, the installation of a vertical pipeline from top to bottom flow, which may lead to evacuation and so on.

　　2. Failure during operation.

　　After a period of initial commissioning and normal operation, the operation of the common failures are: flow sensor wall attached layer, lightning strikes and electric shock, changes in environmental conditions.

　　Lightning strikes in the line induced transient high voltage and surge current, when entering the instrument will damage the instrument. There are three ways to introduce lightning strikes into the instrument: the power line, the flow signal line between the sensor spoon converter and the excitation line.

　　3. The instrument itself is defective.

　　When the liquid flow rate is too low, the measured liquid contains tiny bubbles, when the bubbles rise to the top of the pipe, the bubbles will gradually be sucked out. Electromagnetic flowmeter will change the smooth area of the liquid, when there is a large amount of gas will produce interference signals, affecting the measurement accuracy.