Typical fault diagnosis and treatment
1. No flow output. Check if there is a fault in the power supply section, test the power supply voltage is normal, test the fuse off, check whether the sensor arrow is in line with the flow direction of the fluid, and replace the sensor installation direction if it is inconsistent; check whether the sensor is full of fluid, if there is no full fluid, replace the pipeline or install it vertically. .
2. The signal is getting smaller or smaller. Test whether the insulation between the two electrodes is broken or short-circuited. The resistance between the two electrodes is normally between (70 and 100) Ω. The inner wall of the measuring tube may be dirty. The electrodes should be cleaned and wiped. Do not scratch the inner lining. Measure the lining of the tube for damage, and replace it if it is damaged.
3. The zero point is unstable. Check whether the medium is full of air bubbles in the measuring tube and in the medium. If air bubbles exist, install an air eliminator upstream. If it is installed horizontally, it can be changed to vertical installation. Check whether the instrument ground is intact. If it is not good, perform three-level grounding (grounding Resistance ≤ 100Ω); Check the conductivity of the medium should not be less than 5μs/cm; Check whether the media is deposited in the measuring tube, and be careful not to scratch the lining.
4. The flow indicator does not match the actual value. Check whether the fluid in the sensor is full of tubes, with or without bubbles, if there is air bubbles, install an air eliminator upstream; check whether each grounding condition is good; check whether there are valves upstream of the flowmeter; if so, move to the downstream or make it fully open. Check whether the converter range setting is correct. If not, reset the correct range.
5. The indicator fluctuates within a certain range. Check if the environmental conditions change, such as new interference sources and other magnetic sources or vibrations that affect the normal operation of the instrument, remove the interference or displace the flowmeter in time; check the test signal cable, and perform end treatment with insulating tape. The conductors, the inner shield, the outer shield, and the housing do not contact each other.
Electromagnetic flow meters used to measure the flow of fluid must be conductive, so non-conductive gas, steam, oil, copper and other substances can not use electromagnetic flowmeter to measure the flow.