Siemens QRB3 Photocell/ Flame Detector

QRB3 Photo-resistive flame detector for the supervision of oil flame in the visible light spectrum. These flame detectors are used primarily in connection with burner controls for small burners.

With this type of flame supervision, the radiation of oil flame in the visible light spectrum is used for generating the flame signal.

The light-sensitive element is a photoresistor.

When there is no light, the detector′s resistance is in the MΩrange.

The resistance drops as the intensity of illumination increases (kΩrange).

In contrast to the selenium photocell of the RAR… detectors, glowing firebrick in the combustion chamber can be detected.