TEL: 0755-2955 6666
Technology Service
Service Technical articles

Maintenance of Electromagnetic Flowmeter

Date: 2019-03-19
浏览次数: 2

1. Daily maintenance

Only periodic visual inspection of the instrument is required to check the surrounding environment of the instrument, remove dust and dirt, ensure no water and other substances, check whether the wiring is in good condition, and check whether there is any newly installed strong electromagnetic field equipment or newly installed wires crossing the instrument nearby.

If the measuring medium is easy to contaminate the electrode or deposit and scale in the measuring tube wall, it shall be cleaned and cleaned regularly.

2, fault finding

When the electromagnetic flowmeter is put into operation or normally put into operation for a period of time, if it is found that the meter is not working normally, the external conditions of the flowmeter shall be checked first, such as whether the power supply is in good condition, whether the pipeline is leaking or in a non-full state, whether there are bubbles in the pipeline, whether the signal cable is damaged, and whether the output signal of the converter (i.e. the input loop of the rear instrument) is open.  Remember to dismantle and repair the flowmeter blindly.

3. Sensor Inspection

Test equipment: one 500MΩ insulation resistance tester and one multimeter.

Test steps:

(1) When the pipeline is filled with medium, use a multimeter to measure the resistance value between terminals A, B and C. The resistance values between A-C and B-C should be equal.  If the difference is more than 1 time, it may be that the electrode leaks and condensed water is adsorbed on the outer wall of the measuring tube or in the junction box.

(2) When the lining is dry, measure the insulation resistance between A-C and B-C with MΩ meter (it should be greater than 200MΩ).  Then use a multimeter to measure the resistances of terminals A and B and the two electrodes in the measuring tube (which should be in short-circuit communication state).  If the insulation resistance is very small, indicating electrode leakage, the entire flowmeter should be returned to the factory for maintenance.  If the insulation drops but there is still more than 50MΩ and the inspection result in step (1) is normal, it may be that the outer wall of the measuring tube is affected with damp, and the inside of the shell can be dried by a hot air blower.

(3) Use a multimeter to measure the resistance between X and Y. If the resistance exceeds 200Ω, the excitation coil and its lead wire may be open or have poor contact.  Remove the terminal board for inspection.

(4) Check the insulation resistance between X, Y and C above 200MΩ. If it drops, dry the inside of the shell with hot air.  In actual operation, the decrease of coil insulation will lead to the increase of measurement error and unstable instrument output signal.

(5) If it is determined that the sensor is faulty, please contact the manufacturer of the electromagnetic flowmeter. Generally, the problem cannot be solved at the site and needs to be repaired by the manufacturer.

4. Converter Inspection

If it is determined that the converter is faulty, please contact the manufacturer of the electromagnetic flowmeter if there is no problem after checking the external reasons. The manufacturer will generally replace the circuit board to solve the problem.

Scan WeChat QR Code
Scan two-dimensional code of mobile phone
Customer service email
400-888-9999 全国免费24小时客服热线
Address: C1-902, Innovation Building, 182 Science Avenue, Guangzhou Science City | TEL:020-82029606 | E-mail:290268806
Copyright ©2019 - 2020 Guangzhou fangshi instrument co., ltd.








  • 18988841997




Return to top