Description:

The Siemens QRA4.U UV flame detector is used in burner control and combustion safety systems. Commonly installed in industrial boilers, gas burners, oil-fired systems, and combustion control units. Maintenance teams, OEMs, and system integrators use this part for replacement, retrofit, and flame safety monitoring.

Applications:

The Siemens QRA4.U UV flame detector is used in industrial and commercial combustion systems to monitor and verify the presence of flame in gas and oil burners. It is widely deployed in boiler systems, furnaces, thermal processing equipment, and power generation units where safe burner operation is critical. The detector ensures reliable flame supervision, ignition verification, and shutdown safety by detecting ultraviolet radiation emitted from combustion flames. 

Technical Specifications:

• Manufacturer: Siemens
• Model / Part Number: QRA4.U
• Product Type: UV Flame Detector
• Detection Type: Ultraviolet (UV) flame sensing
• Detection Range: Approx. 190–270 nm wavelength
• Application: Gas and oil flame supervision
• Mounting: Direct burner or boiler mounting (threaded connection)
• Connection Thread: ¾”-14 NPSM
• Cable Length: Approx. 1.8 m
• Operating Temperature: -20°C to +60°C
• Protection Rating: IP54 (installation dependent)
• Max. Combustion Chamber Pressure: 150 mbar
• Weight: Approx. 0.18 kg
• Compatibility: Siemens burner controllers (LFL, LME, LGB, LMV series)

Common Replacements:

• Siemens QRA4M.U Flame Detector
• Siemens QRA10M.C UV Flame Detector
• Beckett QRA4.U Compatible Flame Sensor