ISEN Side-Mounted Level Switch is a compact mechanical level detection solution designed to monitor liquid levels in tanks and process vessels. It uses a float ball that moves with the liquid level and mechanically actuates a reed switch or microswitch to provide an ON/OFF signal for alarm indication, level control, or remote monitoring.
The switch can be installed horizontally through the side wall of a tank, while the product family also includes top-mounted configurations for vertical installation. Its simple construction, reliable switching mechanism, and variety of materials and process connections make it suitable for applications across water treatment, petrochemical, power generation, food processing, and other industrial systems.
How a Side-Mounted Float Level Switch Works
The ISEN Side-Mounted Level Switch operates through a straightforward float-and-switch mechanism. As the liquid level rises or falls, the float ball moves up or down because of liquid buoyancy. This movement is transferred through the lever arm to the switching mechanism inside the junction box.
When the float reaches its switching position, the magnet at the end of the arm interacts with the internal reed switch or microswitch. The switch then changes its electrical state, producing an ON or OFF signal.
This signal can be used to trigger a level alarm, stop or start equipment, or send a level status to a remote control system. The exact control function depends on the wiring configuration and whether the contact is used as normally open or normally closed.
The catalog describes the float and linkage mechanism as operating relative to the horizontal line, with switching occurring when the float reaches the specified horizontal position. This mechanical principle allows level detection without continuously measuring the liquid level electronically.
Because the sensing mechanism is based on physical float movement, the switch provides a simple solution when the application only requires reliable level status rather than a continuous analog level measurement.
Key Features of the Side-Mounted Level Switch
The ISEN Side-Mounted Level Switch is designed around simplicity and dependable mechanical operation. The catalog highlights several features that make it suitable for industrial liquid level monitoring.
One important advantage is its simple structure. The float moves according to liquid buoyancy and directly operates the switching mechanism, reducing the complexity of the sensing system.
The control section is also isolated from the measured liquid medium. This separation allows the switch to be used in applications involving elevated temperature and pressure, provided the selected configuration is suitable for the actual process conditions.
Another benefit is its resistance to the effects of viscous liquids. The catalog specifically notes that the switch is not easily affected by viscous liquids, which can be important when monitoring industrial fluids that are thicker than ordinary water.
The product family also supports multiple construction materials and connection methods. Depending on the selected configuration, the wetted components can use stainless steel, polypropylene, or other specified materials, while process connections include threaded and flange options.
The switching mechanism is designed for repeated operation, with the catalog specifying a contact action lifespan of up to 1 million cycles. This makes the device suitable for applications where the level switch is expected to operate repeatedly over an extended period.
Materials, Float Options and Process Connections
Different industrial liquids require different construction materials. The ISEN Side-Mounted Level Switch can therefore be configured with several material options.
The catalog lists SUS304 and SUS316L stainless steel for the product structure and stem, depending on the configuration. Polypropylene is also available for applications where a PP construction is appropriate.
Float materials include 304 stainless steel, 316L stainless steel, titanium alloy, and PP polypropylene. This range allows the switch to be selected according to the liquid characteristics and process environment.
Several float dimensions are also available, including approximately 42 × 125 mm, 50 × 150 mm, and 75 × 120 mm, with the final selection depending on the required installation and measurement range.
For process connections, the catalog lists options such as 1-1/2-inch PT thread, G1 thread, G1/2 thread, DN50 flange, DN80 flange, and square flange, with customized connections available.
The product family includes standard threaded versions, flanged versions, PP versions, high-temperature configurations, and all-stainless-steel constructions. This makes it possible to configure the level switch for different tank designs and process requirements rather than using a single fixed construction for every application.
Technical Specifications and Switching Output
The ISEN Side-Mounted Level Switch is primarily a discrete level detection device. Instead of providing a continuous 4–20 mA level measurement, its switching mechanism provides a contact output that changes state when the float reaches its operating position.
The catalog specifies an output contact rating of 5A/220VAC for the listed configurations, with an SPDT contact form. This allows the switch to be wired for normally open or normally closed operation depending on the required control logic.
Typical standard configurations have an applicable liquid specific gravity of approximately 0.55 g/cm³ or higher, according to the catalog specifications. The actual suitability should be checked against the selected float, liquid properties, and operating conditions.
Temperature capability depends on the selected construction. Standard configurations are listed around -20 to 80°C, while other configurations extend the operating range. The catalog also identifies high-temperature options, including configurations that can be customized for temperatures up to approximately 350°C.
For installations requiring additional environmental protection, all-stainless-steel versions are available. The catalog identifies explosion-proof configurations for certain stainless-steel side-mounted constructions, including an ExdIICT6 rating.
The junction box can also be selected from different materials, including ABS, aluminum alloy, stainless steel, and PP, depending on the configuration.
Installation Guidelines for Reliable Level Detection
Correct installation is essential for stable operation of a float level switch. Because the device responds to physical movement of the float, external liquid turbulence or incorrect positioning can cause unwanted switching.
The catalog recommends installing the switch away from the tank inlet or outlet. Strong liquid movement near an inlet or outlet can cause fluctuations in the liquid surface and potentially result in false switching.
For tanks or vessels with significant agitation, the catalog recommends using anti-wave pipes or baffles to reduce excessive movement around the float.
The connection pipe and its dimensions should also be selected so that they do not restrict the movement of the float and linkage mechanism. The float needs sufficient space to move through its operating range.
The control circuit should not exceed the rated contact capacity. The catalog specifies that the control load must remain below the contact rating to avoid overloading the switching mechanism.
During installation, attention should also be paid to the movement angle of the float and linkage. The catalog specifies an operating movement range of approximately ±14 degrees relative to the horizontal line, with the switch actuating when the float reaches the horizontal position.
These details are especially important when the switch is used for automatic pump control or alarm functions, where unstable switching could cause unnecessary equipment cycling.
Industrial Applications of Side-Mounted Level Switches
ISEN Side-Mounted Level Switches are intended for a wide range of liquid level detection and control applications. The catalog identifies applications across petrochemical, power generation, food processing, water treatment, and electrical engineering.
- In petrochemical applications, the switch can be used for liquid level detection in storage tanks and for level control in chemical storage tanks and reactors.
- In power generation equipment, it can be applied to liquid level monitoring in boilers, towers, and other process equipment.
- For water treatment systems, the float switch can provide simple high-level or low-level status signals for tanks and reservoirs. The switching output can also be connected to pumps, alarms, or control systems depending on the required control logic.
- In food processing and other industrial environments, the available stainless-steel and PP construction options provide flexibility for selecting a configuration compatible with the process medium and installation environment.
The switch is particularly suitable when the application requires a simple, direct ON/OFF level signal rather than continuous level measurement. Its compact construction, mechanical switching principle, multiple materials, and available threaded or flange connections make it adaptable to different industrial tanks and vessels.
For applications requiring continuous level information, a different type of level transmitter may be more appropriate. For applications requiring reliable point-level detection, the ISEN Side-Mounted Level Switch provides a practical solution.
Valvelink can help select the appropriate ISEN Side-Mounted Level Switch configuration based on the liquid medium, specific gravity, tank connection, operating temperature, required switching function, material, and installation position.
