SW-21 Compact Magnetic Switch for Magnetic Level Indicators
SW-21 compact magnetic switch is designed as an external switching accessory for the Flap-11 magnetic level indicator series. It helps users add remote alarm, automatic signaling, and liquid level control functions to local level indication systems. Because of its compact size, it is especially useful in installations where space is limited.
The switch works together with the magnetic float inside the magnetic level indicator. As the liquid level rises or falls, the float moves with it. When the permanent magnet inside the float approaches the switch, it activates the reed switch and changes the signal status. The control system then receives this signal and uses it for alarm, switching, or control functions.
Compact Design with Reliable Reed Switch Performance
A key feature of the SW-21 compact magnetic switch is its slim and lightweight structure. It has a width of 35 mm and a length of 120 mm, which makes installation easier in restricted spaces. This compact design helps users add level alarm functionality without taking up much room around the indicator.
The device uses an imported high-quality high-power reed switch as its core component. This helps improve switching reliability and service life. Because the switching action depends on magnetic movement rather than direct contact with the process liquid, the system remains simple and dependable during long-term operation.
Durable Structure for Industrial and Hazardous Areas
The chamber is made of 304 stainless steel, which helps improve corrosion resistance and durability in industrial environments. The device also supports IP66/IP67 protection, so it can perform reliably in wet, dusty, and outdoor field conditions.
SW-21 compact magnetic switch supports SIL2 / SIL3 functional safety requirements. It is also certified for both intrinsically safe and flameproof explosion protection. In addition, Jiwei holds a utility patent for this compact design. These features make it a practical choice for industrial plants and hazardous-area applications that require dependable switching performance in a smaller housing.
Typical Applications
This compact magnetic switch is widely used with Flap-11 magnetic level indicators in tanks, process vessels, utility systems, and industrial liquid storage applications. It is especially useful when users need remote alarm and control functions in installations with limited space. It also works well in systems that require reliable switching performance together with compact accessory design.
For other magnetic level accessories, see the [SW-11 Magnetic Switch] and the [Reed-11 / Reed-21S Remote Transmitter]. The switch is also designed to work with the [Flap-11 magnetic level indicator] series.
