Hi, this is little control in the butler, the common faults occurring in the use of electromagnetic flowmeter, may be due to the components damage caused as a result of the instrument itself, also may be due to improper selection, improper installation, environmental conditions, factors such as fluid properties, are generally divided into two types: installation and debugging of fault (failure) during commissioning period and normal operation of the fault (run-time failure),

During commissioning period of (1) failure debugging expect failure generally appear in the instrument installation and debugging stage, once ruled out, under the same conditions after general won't appear, during commissioning period of common failures generally by improper installation, environmental influence and the characteristics of fluid causes, such as
1) installation of electromagnetic flow sensor installation location is usually caused by incorrect fault, common such as sensor installed on the easy accumulation of gas piping high; Or installed on the top-down vertical tube, may appear empty; Or sensors after no back pressure, fluid directly discharged into the atmosphere and form the measuring tube not filled tube,
2) is usually main pipeline stray current interference environment, space is strong electromagnetic interference, large motor magnetic interference, such as pipeline stray current interference usually take good separate grounding protection can obtain satisfactory results, but if strong stray current (such as electrolytic workshop pipeline, sometimes in two electrode induction ac peak potential Vpp can be as high as 1 v), still need to take other measures and flow sensor and pipe insulation and so on, generally by the signal cable into space electromagnetic interference, usually adopts single layer or multi-layer shielding protected,
3) fluid on the uniform distribution of tiny air bubbles in the liquid to be measured is usually does not affect the normal work of the electromagnetic flowmeter, but with the increase of air bubbles, the volatility meter output signal, if the bubble is big enough to cover the entire electrode surface, as the bubble through the electrodes can make electrode circuit instantaneous trip and make the output signals appear larger fluctuation,

(2) the run-time failure run-time failure is electromagnetic flowmeter by the commissioning and normal operation after a period of fault, common run-time failures generally by the flow sensor wall adhesion layer, lightning strikes and factors, such as environmental conditions change
1) sensor inner surface adhesion layer due to the electromagnetic flow meter used to measure the dirt fluid, run after a period of time, often on the inner wall of the sensor, the accumulation of adhesive layer and fault, the fault is often caused by adhesion layer conductivity is too big or too small, if the attachments as the insulating layer, the electrode loop will be cut-off, instrument can not work normally; If adhesion layer conductivity is significantly higher than fluid conductivity, the electrode will appear short circuit loop, instrument can not work normally, so, should keep clear of electromagnetic flowmeter measurement tube adherent fouling layer,
2) lightning strike by lightning easily induced in the instrument line out high voltage and surge current, the meter is damaged, it mainly through the power cord or excitation coil or the flow line between the sensor and converter approaches introduced, particularly from the control room power supply cord into accounts for the vast majority of,
3) to the changing environmental conditions during the debug due to environmental conditions is good (for example, no interference sources), flow meter works well, at this point is often easy to neglect the installation conditions (such as grounding is not how good, in this case, once the changing environmental conditions, run during the emergence of a new interference sources (such as electric welding on the pipe near the flowmeter, installed near the large transformer, etc.), will interfere with the normal work of the instrument, the output of the meter output signal will fluctuate,

Well, the content of this issue will be here, what we want can leave a message at any time, welcome the attention ah,