The Seojin Instech ST-600 Series Float Type Level Transmitter, configuration model code ST-600-A-1-A-4-A-3-F, is 100% designed, engineered, and manufactured in South Korea by Seojin Instech Co., Ltd. Recognized as an industry-standard continuous liquid level measurement solution, the ST-600 series offers high accuracy, rugged mechanical durability, and long-term operating stability across thermal power plants, water treatment facilities, industrial steam boiler systems, and petrochemical fuel storage tanks.

The operating principle relies on Archimedean buoyancy combined with non-contact magnetic actuation. Inside a heavy-duty stainless steel SUS304 stem, a linear circuit consisting of precision reed switches and resistors is hermetically sealed and serially arranged at standardized intervals of 10 to 15 mm. A cylindrical float equipped with an internal permanent magnet travels smoothly along the stem as the liquid level rises or falls. The magnetic field emitted by the float closes the adjacent reed switches, sequentially altering the total resistance of the circuit proportional to the liquid height. The integrated electronic head converter instantaneously transforms this resistance change into an industrial-standard 4 ~ 20mA DC analog signal (2-wire loop powered at 24VDC), delivering reliable, interference-immune level telemetry back to plant PLCs, DCS controllers, or digital panel indicators.

The ST-600-A-1-A-4-A-3-F configuration provides distinct industrial advantages: a standardized 0 to 4-meter measuring range (code 4), making it suitable for a wide variety of medium to large-capacity storage vessels. All wetted components—including the guide stem, magnetic float, float stoppers, and mounting flange—are fabricated from premium SUS304 stainless steel (code A), providing superior resistance to chemical corrosion, oxidation, and mechanical wear under working pressures up to 10 kgf/cm² and temperatures up to 100 °C. The electrical terminal housing is cast from heavy-duty ADC12 aluminum alloy with an industrial protective finish certified to IP65 weatherproof standards (code A). Outfitted with a standardized JIS 10K 80A 6t FF flange (code 1) and a dedicated electrical conduit connection (code F), the ST-600 ensures hermetic sealing against environmental moisture, offering seamless field installation and virtually maintenance-free performance.

• Manufacturer: Seojin Instech Co., Ltd.
• Origin: 100% Korea (South Korea)
• Product Series: Float Type Level Transmitter (ST-600 Series)
• Configuration Model Code: ST-600-A-1-A-4-A-3-F
• Measurement Principle: Magnetic float actuating a series of internal reed switches and precision resistors
• Measuring Part Length: 0 ~ 4 Meters (Code 4)
• Output Signal: 4 ~ 20 mA DC (2-Wire Loop Powered)
• Operating Power Supply: 15 ~ 32V DC (Standard 24V DC)
• Measurement Resolution: Approx. 10 mm ~ 15 mm
• Measurement Accuracy: ±10 mm
• Field Calibration: Integrated Zero and Span trimmers located on the internal converter board
• Wet Part Material (Stem, Float, Flange, Stopper): Stainless Steel SUS304 / 304SS (Code A)
• Magnetic Float Style & Dimension: Cylindrical SUS304 float Ø79 mm × 90 mm Height (or Ø75 mm option)
• Minimum Medium Specific Gravity: 0.85 g/cm³ and above
• Process Operating Temperature Range: -10 °C to +100 °C
• Maximum Vessel Operating Pressure: Up to 10 kgf/cm² (~10 bar)
• Process Mounting Connection: JIS 10K 80A 6t FF Flange (Code 1)
• Electrical Enclosure: Weatherproof Housing (Code A), heavy-duty die-cast aluminum ADC12 with powder coating
• Enclosure Protection Rating: IP65 according to IEC 60529
• Conduit Cable Connection: Option F conduit connection (PF 1/2" or PF 3/4")
• Applicable Industries: Thermal power stations and industrial boiler plants (feedwater and condensate tanks), municipal water treatment and industrial wastewater plants, standby generator diesel storage tanks (DO/FO), centralized lubrication systems, industrial cooling tower basins, mild chemical storage tanks, marine shipboard tanks, and commercial Building Management Systems (BMS).