External-Mount Level Sensor: A New Choice for Water Level Control in Metal Tanks [Dayu Electronics]
For metal tanks with outer diameters of ∮500mm and ∮1200mm and wall thicknesses of approximately 4mm, the solution for water level control using external-mount level switches is as follows:
1. Overview of External-Mount Level Switches
External-mount level switches are a new type of level monitoring and alarm device, mainly used to monitor the liquid level in storage tanks, providing high/low level alarms or detecting the presence of media in pipelines (dry-run protection). This device is especially suitable for liquid level process control in industries such as pharmaceuticals, petroleum, chemical, electric power, and food. External-mount level switches are available in ultrasonic and sonar types. The external-mount ultrasonic level switch detects liquid level through high-frequency ultrasonic pulses generated by its sensor (probe).
2. Features of External-Mount Ultrasonic Level Switches
Non-contact measurement: The sensor (probe) of the external-mount ultrasonic level switch is installed on the outer wall of the container to be measured, without direct contact with the medium, achieving non-contact measurement and avoiding the drawbacks of traditional level switches that require opening holes or hot work on the container wall.
High measurement accuracy: The external-mount ultrasonic level switch accurately determines whether liquid is present inside the container at the monitoring point by detecting the reflection characteristics of ultrasonic pulses in the container wall and liquid, with measurement accuracy up to 2mm.
Wide applicability: The external-mount ultrasonic level switch is suitable for containers made of various hard materials, such as metal and non-metal. Its transmitted signal can penetrate tank walls up to 70mm thick, making it suitable for the metal tanks in this example, with diameters from ∮500mm to ∮1200mm and wall thicknesses of approximately 4mm.
3. Applications of External-Mount Ultrasonic Level Switches
Level control: The external-mount ultrasonic level switch can be used to monitor the water level in metal tanks, providing high and low level alarms. By outputting relay signals to downstream electrical equipment or other devices, level monitoring or control can be achieved.
Explosion-proof performance: Some external-mount ultrasonic level switches have explosion-proof features, suitable for explosive gas atmospheres other than coal mines, ensuring safe use in hazardous environments.
4. Installation Precautions
Avoid interference: When installing an external-mount ultrasonic level switch, avoid placing other ultrasonic or electromagnetic devices nearby to prevent mutual interference and false triggering.
Probe alignment: The two probes of the level controller must be arranged horizontally on the tank wall, with a spacing of 1 meter. Avoid welds or similar conditions between the probes, and each probe should also be positioned as far away from welds as possible.
In summary, the external-mount ultrasonic level switch is an ideal choice for water level control in metal tanks. Its non-contact measurement, high accuracy, and wide applicability make it suitable for level control needs across different industries and scenarios.