The Siemens QRA10 Flame Sensor & Detector is an ultraviolet (UV) flame detector used for monitoring gas flames and yellow or blue oil flames in industrial burner systems. It detects the UV radiation emitted by a flame and sends a signal to the burner control system to confirm safe burner operation.

The detector is designed for intermittent burner operation, making it suitable for combustion systems that shut down periodically, such as industrial boilers and process burners.

The QRA10 features a robust die-cast aluminum housing, which protects the internal UV cell from harsh industrial environments. It includes a mounting coupling for installation on a viewing tube or burner housing and provides a connection for cooling air to prevent overheating and soot accumulation on the lens.

This detector is widely used with Siemens burner control units such as LFL, LAL, LFE, LME, and LMV series controllers, making it a versatile solution for flame monitoring in industrial combustion equipment.

Key Features

• Designed for oil and gas industrial burners

• High-sensitivity ultraviolet (UV) flame detection

• Detects UV radiation emitted by gas and oil flames

• Suitable for intermittent burner operation

• Rugged die-cast aluminum housing for industrial environments

• Connection for cooling air to maintain sensor performance

• Compatible with multiple Siemens burner controllers

• Replaceable UV sensor tube for easy maintenance

• Reliable flame supervision for safe burner operation

Applications

• Industrial gas burners

• Industrial oil burners

• Dual-fuel combustion systems

• Steam boilers and hot water boilers

• Industrial furnaces and ovens

• Thermal processing equipment

• Process heating systems

Why Choose Siemens QRA10 Flame Detector?

• Trusted Siemens combustion safety technology

• Highly accurate UV flame detection

• Reliable flame monitoring for industrial burners

• Durable design for harsh industrial environments

• Compatible with many Siemens burner control systems

• Long service life with replaceable UV cell

Technical Description

The Siemens QRA10 Flame Detector operates using an ultraviolet (UV) sensor that detects radiation emitted by burner flames in the wavelength range of approximately 190–270 nm. When the detector senses sufficient UV radiation, it generates an electrical signal indicating the presence of a flame.

This signal is transmitted to the burner control unit, which verifies flame presence during ignition and burner operation. If the flame signal disappears during operation, the burner control system initiates a safety shutdown to prevent unsafe combustion conditions.

The detector is designed with a 1-inch mounting coupling and bayonet connection, allowing easy installation on a burner viewing tube or combustion chamber inspection port. A cooling air connection helps maintain the internal temperature of the UV cell and prevents soot buildup on the detector window.

The internal UV cell typically has a service life of approximately 10,000 operating hours, after which replacement of the UV tube is recommended to maintain accurate flame detection.

Technical Specifications