Siemens QRA53.G27: High-Sensitivity UV Flame Detector
The Siemens QRA53.G27 is a high-sensitivity UV flame detector designed for the supervision of gas and oil flames, as well as for checking the ignition spark in industrial burner applications. This ultraviolet sensor is specifically engineered to operate in conjunction with Siemens burner controls, providing a critical safety link in the combustion process. It is particularly suited for use on large-scale burners in continuous or intermittent operation where precise flame detection is mandatory.
The QRA53.G27 utilizes a sophisticated UV-sensitive cell that reacts exclusively to the specific light spectrum of a flame, effectively ignoring background radiation from hot refractory brickwork or other infrared sources.
Technical Specifications and Operating Characteristics
Based on official Siemens technical data sheets, the QRA53.G27 features the following characteristics:
-
Sensing Technology: Ultraviolet (UV) radiation sensor for gas and oil flames.
-
Sensitivity Range: High-sensitivity version, optimized for specific industrial combustion requirements.
-
Enclosure Design: Die-cast aluminum housing with a high-grade finish for thermal and mechanical durability.
-
Ambient Temperature: Rated for operation from -20 °C to +60 °C.
-
Degree of Protection: IP54-rated (IP65 achievable with additional sealing) to withstand demanding boiler room environments.
-
Cooling Air Connection: Integrated connection for cooling air to prevent overheating and soot deposition on the lens.
-
Compatibility: Fully compatible with Siemens LGK… and LGI… burner control units.
Strategic Benefits for Industrial Combustion Systems
The QRA53.G27 offers essential advantages for high-tier thermal energy infrastructures:
-
Fail-Safe Operation: Engineered to meet the highest safety standards, ensuring immediate shutdown of the fuel supply upon flame failure.
-
Extreme Robustness: The metal housing and industrial-grade internals are built to withstand the vibration and temperature fluctuations typical of heavy-duty burner fronts.
-
Accurate Signal Discrimination: Highly selective sensor technology ensures that the detector only responds to the flame’s UV spectrum, preventing false signals from heat radiation.
-
Versatile Mounting: Designed for easy integration with specialized mounting flanges and cooling air systems, allowing for precise alignment with the combustion zone.
