Siemens Infrared Flame Detector QRI

Siemens Infrared Flame Detector QRI Series

Siemens QRI Series infrared flame detectors are designed for monitoring gas, oil, and other flames that emit infrared radiation. These detectors operate with Siemens LMV5 burner controls to provide flame supervision in industrial combustion applications.

Key Features

• Infrared-sensitive flame detection element with a spectral sensitivity range of approximately 1–3 µm
• Integrated flame signal amplifier
• Available for frontal and lateral flame illumination
• Compatible with Siemens LMV5 burner control systems
• Suitable for continuous and intermittent burner operation
• Analog flame signal output of DC 0–5 V
• Impact-resistant black plastic housing with a dust-tight lens
• IP54 degree of protection

Operating Principle

Siemens QRI flame detectors use an infrared-sensitive photoresistor to detect changes in infrared radiation emitted by the flame.

The detector converts these radiation variations into an electrical flame signal that is transmitted to the burner control. Electronic filtering suppresses constant radiation and interference associated with mains-frequency harmonics.

Available Models

• QRI2A2.B180B – Frontal illumination flame detector
• QRI2B2.B180B – Lateral illumination flame detector
• QRI2B2.B180B1 – Lateral illumination detector supplied with a straight flange and clamp

Applications

Siemens QRI infrared flame detectors are suitable for flame supervision in industrial boilers, gas and oil burners, and industrial heating systems.

These detectors must be used with compatible burner control equipment and installed according to Siemens technical and safety instructions.

Installation Note: The detector should be positioned behind the burner's baffle plate to minimize interference from hot surfaces and other infrared radiation sources. Installation and safety testing must be performed by qualified personnel.