The Pune Techtrol Model SPA-MLG Transmitter Assembly (Factory Identification: Sr. No. 161733628, Ref. No. 15228.000/16-17), engineered and manufactured by Pune Techtrol Pvt. Ltd. in Pune, India, is an industrial-grade continuous level sensing solution designed to mount externally alongside Magnetic Level Gauges (MLG).

Operating Principle of the Reed Chain Level Transmitter:
The SPA-MLG transmitter assembly is clamped securely onto the non-magnetic bypass measuring chamber of an existing Magnetic Level Gauge using heavy-duty stainless steel mounting clamps. Inside the sealed sensor stem lies a continuous chain of precision reed switches paired with an equidistant resistor network:
- As the liquid level shifts inside the process vessel, the internal magnetic float moves in tandem due to buoyant force.
- The focused magnetic field of the permanent magnet inside the float acts through the chamber wall, magnetically closing the adjacent reed switch contacts corresponding to that exact elevation.
- This contact closure taps into a linear resistive voltage divider network, dynamically varying the total output resistance. The head-mounted electronic transmitter converts this continuous resistance change into a standard 4 to 20 mA analog current loop powered by 24 VDC, transmitting real-time level data to PLCs, DCS architectures, or remote digital indicators.

Key Engineering Features & Operational Advantages:
- Extended 2500 mm Measuring Range (CC Distance 2500mm): Built to custom engineering specifications with a calibrated center-to-center (CC) active length of 2500 mm (2.5 meters), perfectly tailored for tall process vessels, large vertical tanks, and bulk storage vessels.
- Non-Intrusive, Safe Architecture: Because the sensor stem is mounted entirely outside the fluid containment pipe, the electrical system never contacts hazardous, toxic, flammable, or pressurized media. Initial mounting, wiring, calibration, and routine servicing are conducted with zero risk of fluid release and without interrupting plant production.
- High Process Temperature Resilience Up to 150°C: Thermally isolated engineering enables the assembly to operate continuously against chamber surface temperatures reaching up to 150°C, making it suitable for boiler condensate lines, thermal oil reservoirs, and hot utility tanks.
- Weatherproof Cast Aluminum Terminal Enclosure: Housed in an IP66-rated cast aluminum termination enclosure coated with protective industrial enamel. Equipped with a PG 9 cable gland entry, it ensures long-term operational integrity against driving rain, dust, and coastal humidity.
- Supplied Heavy-Duty Mounting Hardware: Shipped complete with factory-matched mounting clamps, allowing field technicians to mount and align the transmitter stem to the bypass chamber quickly and accurately.

Target Industrial Sectors & Applications:
- Petrochemical Refineries & Oil Depots: Continuous level telemetry on hydrocarbon storage tanks, chemical holding tanks, and water-oil knockout drums.
- Power Generation & Utilities: Monitoring boiler feedwater drums, deaerator storage vessels, condensate return tanks, and flash tanks.
- Chemical & Fertilizer Plants: Continuous monitoring of aggressive acids, caustics, liquid ammonia, and volatile organic compounds.
- Food, Beverage & Pharmaceutical Facilities: Syrup storage tanks, fermentation vessels, industrial CIP reservoirs, and pure water storage.
- Water Treatment & Municipal Infrastructure: Pressure vessel level tracking, industrial clarifiers, and coagulant chemical bulk storage.

• Manufacturer: Pune Techtrol (Pune Techtrol Pvt. Ltd.)
• Country of Origin: 100% India (Made in India)
• Product Line: Transmitter Assembly for Magnetic Level Gauges (SPA-MLG Series)
• Model Designation: SPA-MLG
• Manufacturing Serial Number: Sr. No. 161733628
• Factory Order / Reference Number: Sr.No161733628, 15228.000/16-17
• Operating Principle: Reed Switch and Resistor Network Chain (Reed Chain Type)
• Center-to-Center Measuring Distance (CC Distance): 2500 mm (2.5 meters)
• Linear Resolution: ±12 mm (Standard resolution configuration)
• Output Telemetry: 4 to 20 mA DC current loop proportional to liquid level
• Power Supply Voltage: 24 VDC nominal
• Terminal Enclosure Metallurgy: Die-cast Aluminum (Cast Al), weatherproof enameled finish
• Ingress Protection Rating: IP66 compliant with IEC/EN 60529 (dust-tight and protected against water jets)
• Cable Conduit Connection: PG 9 cable gland fitting
• Maximum Process Temperature: Up to 150°C (302°F)
• Mechanical Mounting Clamps: Supplied complete (Heavy-duty clamp-on brackets)
• Hazardous Area / Intrinsic Safety: Non-Ex rated (Not Provided)
• Local Digital Display: None integrated (Not Provided / Blind Transmitter)
• Mounting Profile: Non-intrusive external clamp-on to MLG chamber
• Quality & Manufacturing Standards: ISO 9001:2015 certified, CE compliant.