Analysis and solution of common faults of radar level sensor
The fault of radar level gauge is often caused by many factors such as selection, installation, production conditions and instrument itself. The following are several factors that affect radar level measurement:
1. Type, size and material of radar level gauge antenna. The horn antenna has a larger measuring range than the rod antenna, and the antenna material is PTFE. The antenna size is too small, and it is easy to lose wave when measuring the bottom of the tank.
2. The installation is improper. If the nozzle is too long, the antenna does not extend the nozzle 10mm, the inner wall of the nozzle is not smooth, there are burr welds, and the radar level gauge is installed at the bottom port.
3. The measured liquid surface conditions are turbulence, agitation or foam.
4. Influence of dielectric constant. The dielectric constant of solid mineral and powder is low, and the microwave reflection intensity is weak.
5. The effect of condensation. Although the effect of water vapor on radar waves is very small, it will cause some condensation in cold weather and affect the normal operation of the level meter. The test results show that the radar level meter with rod antenna has less effect on resisting condensation caused by water vapor.
6. Dirt on the antenna. Scarring on the horn antenna will weaken the energy of the microwave, or even lose the wave, so that the meter can not be measured, so the antenna of the radar level meter must be kept clean. When cleaning the scar or dust, pay attention to protect the transmitter head, so as not to damage and affect the measurement.
7. Dust. Although microwaves can penetrate the influence of dust, in some cases of extreme dust severity, the raised dust may adhere to the radar wave emission electrode, resulting in the attenuation of the transmitted signal, or even complete loss.
8. Failure of instrument parts. Instrument display panel fault: generally does not affect the 4 ~ 20mA signal sent to the main control room, can be replaced. Instrument circuit board failure: The circuit board inside the radar level gauge can be replaced.
