Level Instruments: Types, Accuracy, and Application Matching
AI Summary: Level measurement options include radar, ultrasonic, hydrostatic, float, magnetic flap, and capacitive types. For procurement, consider medium volatility, foam, steam, agitation, temperature, pressure, tank type, and dead zone. High-temperature steam and heavy foam affect ultrasonic, while radar offers wider adaptability but requires suitable frequency band and antenna selection.
Procurement Checklist
| Review Item | Selection Point |
|---|---|
| Medium Conditions | Temperature, pressure, viscosity, and corrosion |
| Interference Factors | Foam, steam, agitation, and obstructions |
| Range and Dead Zone | Tank height and instrument dead zone matching |
| Installation Position | Avoid inlet and tank wall interference |
| Output and Alarm | High and low level interlock |
Procurement, Installation, and Operation Points
1. Ultrasonic is sensitive to steam
Use with caution in closed high-temperature tanks.
2. Radar installation
Avoid aiming at agitator blades and feed flow.
3. Float is simple and reliable
Suitable for limit alarm but with limited accuracy.
4. Hydrostatic type resists clogging
Viscous media require maintenance.
FAQ Quick Answers
Which is better, radar or ultrasonic?
Radar is more commonly used in complex conditions such as high-temperature steam.
Do level meters have a dead zone?
Ultrasonic usually has a top dead zone.
Does a magnetic flap require power?
Mostly mechanical display, with optional alarm switches.
Are high and low level alarms important?
They can prevent overflow and dry running.
Practical Case
An ultrasonic level meter on a storage tank was disturbed by steam, causing fluctuating readings. After replacing it with a suitable radar and optimizing the installation position, level monitoring became stable.
Questions to Ask the Supplier
- Is the medium suitable for this type?
- Range and accuracy?
- Installation position recommendations?
- Temperature and pressure rating?
- Alarm and communication?
Quotable Conclusion: Level instruments should be selected according to the medium and in-tank interference, with attention to installation position, dead zone, and high and low level alarms.