Ballast Tank Level Sensing on Commercial Submarines

In commercial submarines, ballast tanks help in controlling buoyancy to allow the vessel to submerge or surface. These tanks take in seawater and expels air to increase the submarine’s weight, enabling it to submerge. To rise to the surface, the water in the ballast tanks is expelled by introducing compressed air, increasing the submarine’s buoyancy.

Proper management of these ballast tanks is essential for maintaining the submarine’s stability and operational efficiency. Precise monitoring of water levels within these tanks is necessary to ensure the submarine responds accurately to buoyancy adjustments.

Reed switch-based level sensors provide a reliable solution for monitoring water levels within the ballast tanks and other compartments. These sensors are highly effective in the harsh marine environment, as they are hermetically sealed, ensuring resistance to moisture, pressure, and corrosion. The PCB assembly of reed switches and resistors, in conjunction with a magnet, provides precise potentiometric feedback on the liquid level. This setup ensures real-time monitoring, and helps maintain optimal buoyancy and stability, preventing potential operational hazards.

A magnetized float moves along a vertical tube inside the ballast tank as the water level rises or falls. The tube houses a series of reed switches and resistors spaced at specific intervals. As the float travels up or down with the water level, the magnet activates the reed switches sequentially and the sum of all resistors up to that point is produced at the output. Each switch closure provides feedback, enabling the system to determine the water level accurately. By continuously assessing the water level with high precision, the system ensures optimal ballast tank performance and the submarine’s ability to manoeuvre effectively.

Reed switch-based level sensing in commercial submarines ensures efficient monitoring of water levels, enhancing both safety and operational control. The technology’s reliability in marine environments makes it ideal for precision buoyancy management, ensuring smooth submarine operations.

Application Classification

Applications are classified as Position Sensing, Pulse Counting, Electromagnetic or Relay, Temperature Sensing or Magnet Biasing types. This application is classified as follows and the link gives more information on best practices to help select the most suitable AT band and matching magnet.

Position sensing Type

When an application requires the end position of a movement sensed, or the sensing of a part when it comes into a zone, or when the Continue reading -> Jul 14, 2025

Recommended Products

The Reed Switches and Sensors used in such submarine ballast tank applications need to be robust, durable and efficient in meeting a high life expectancy. Our engineers work hard in life testing our products under various conditions, and our intention is to ensure end product durability and life. Although we wouldn’t want to restrict any of our products for use in only certain applications, the recommended products for use in this application are listed below.

Standard Size Reed Sensor, R2

R2-S Gull-wing SMD Formed Reed SensorR2-S Gull-wing SMD Formed Reed Sensor Pad LayoutR2-F Low Profile SMD Formed Reed SensorR2E-F Low Continue reading -> Jun 18, 2025

Line Voltage switching Reed Switch, LV-1925

Full Length LeadsCropped LeadsSMD Formed LeadsVertical MountingHorizontal Mounting starFeaturesContact Rating Configurable. Ruthenium Continue reading -> Jul 14, 2025

Inductive Load Switch Reed Switch, IL-2022

Full Length LeadsCropped LeadsSMD Formed LeadsLeads Formed for Horizontal MountingLeads Formed for Vertical Continue reading -> Nov 30, 2024