Siemens UV Flame Detector QRA55.E27

Product Details

ENERGY COMBUSTION, Ahmadabad supplying all types of Siemens make Flame Sensors. The Siemens QRA55 is a high-end ultraviolet (UV) flame detector designed for continuous operation (systems running for 24 hours or more without shutdown). It is nearly identical in function to the QRA53, but it features a shorter detector tube length. The QRA55 includes a built-in self-checking mechanism (a motorized shutter) that periodically blocks the UV cell to ensure it has not failed in a "flame-on" state. Full Technical Specifications Feature Specification Detection Type Ultraviolet (UV) Spectral Sensitivity 190 to 270 nm Operating Mode Continuous Operation (Self-checking) Protection Rating IP65 (Dust tight and protected against water jets) Detector Tube Length 69 mm (Short version) Average UV Cell Life Approx. 10,000 operating hours Operating Temperature -20 °C to +60 °C Housing Material Die-cast aluminum Replacement UV Cell AGR4 502 4065 0 Understanding the Model Numbers The suffixes for the QRA55 indicate the voltage and sensitivity level: QRA55.E17: 100–110 V AC, Normal Sensitivity QRA55.E27: 220–240 V AC, Normal Sensitivity QRA55.G17: 100–110 V AC, High Sensitivity QRA55.G27: 220–240 V AC, High Sensitivity Key Features Self-Checking Shutter: An internal stepper motor drives a shutter that tests the UV cell's functionality continuously. This is mandatory for industrial burners that do not cycle daily. Rugged Design: The aluminum housing is highly durable and carries an IP65 rating, making it suitable for demanding industrial environments. Short Tube Advantage: The 69 mm length is ideal for compact burner configurations where a standard 125 mm sensor (like the QRA53) would be too long. Compatible Controls: Primarily used with the LGK16 and LGI16 burner management systems. Installation Requirements Connecting Cable: This sensor requires the AGM19 connecting cable. Mounting: It is typically mounted using the supplied clamp. For high-temperature protection, it is often paired with the AGG06 glass holder. Signal Transmission: Because the signal is low-voltage/low-current, the detector cable should never be run in the same conduit as high-voltage ignition cables or motor power lines to avoid interference. Maintenance Tip The UV cell inside the QRA55 is a consumable part. After approximately 10,000 hours, the cell will lose its "quenching" ability, leading to false flame signals or burner lockout. You can replace just the internal tube (AGR4 502 4065 0) rather than the entire detector to save on maintenance costs.