What are the common faults of flow meters? Posted by : admin / Posted on : Mar 08， 2021

Typical fault diagnosis and treatment
1. No flow output. Check whether the power supply part is faulty, test whether the power supply voltage is normal; test whether the fuse is on or off; check the transmission

Whether the sensor arrow is consistent with the fluid flow, if not, change the sensor installation direction; check whether the sensor is full of fluid, if not

Filled with fluid, replace the pipe or install it vertically.
2. The signal is getting smaller or decreasing suddenly. Test whether the insulation between the two electrodes is broken or short-circuited, and the resistance between the two electrodes is normal at (70

～100)Ω; dirt may be deposited on the inner wall of the measuring tube, the electrode should be cleaned and wiped, and the inner lining should not be scratched. Whether the measuring tube lining

Damaged, if damaged, it should be replaced.
3. The zero point is unstable. Check whether the medium is full of the measuring tube and whether there are bubbles in the medium. If there are bubbles, install a deaerator upstream

If it is installed horizontally, it can be changed to vertical installation; check whether the grounding of the meter is intact. If it is not good, perform three-level grounding (grounding resistance).

≤100Ω); check that the conductivity of the medium should not be less than 5μs/cm; check whether the medium is siltated in the measuring tube, and be careful not to remove

The inner lining is scratched.
4. The flow indication value does not match the actual value. Check whether the fluid in the sensor is full of the tube and whether there are bubbles. If there are bubbles, add them upstream.

Install a degasser; check whether the grounding conditions are good; check whether there is a valve upstream of the flowmeter, if any, move it downstream or make it fully open;

Check whether the converter range setting is correct, if not, reset the correct range.
5. The indicated value fluctuates in a certain interval. Check whether the environmental conditions have changed, such as the appearance of new interference sources and other influences on the normal operation of the instrument

Magnetic source or vibration, etc., the interference should be cleared or the flowmeter should be moved in time; check the test signal cable, and use insulating tape to carry out the end

Make sure that the wires, the inner shielding layer, the outer shielding layer, and the shell do not touch each other.
The fluid used to measure the flow of the electromagnetic flowmeter must be conductive, so non-conductive gas, steam, oil, copper and other substances are not

Electromagnetic flowmeter can be used to measure flow.