Siemens QRB4B-B050B70 Flame Detector

Technical Specifications

DetectionPhotodiode; yellow oil flame
Operating dutyIntermittent
SensitivityHigh; red
Mounting connectionFlange mounting; fittings excluded
Housing68 mm length
Connection50 cm cable; 70 mm stripped; ferruled conductors
ProtectionIP54 housing only
Price:

USD30

Flame detector only

Product Overview

The Siemens QRB4B-B050B70 is the high-sensitivity QRB4 configuration with a 50 cm cable and no supplied mounting fittings. It uses a red 68 mm housing and a photodiode sensing element for yellow oil-flame supervision.

Product Specification

  • High sensitivity; red 68 mm detector housing.
  • Fixed 50 cm cable with 70 mm stripped ends and ferruled conductors.
  • Two-core stranded copper cable, 2 × 0.75 mm².
  • Supplied without a soft mounting plug, flange or clamp.
  • Frontal and 90-degree lateral flame viewing.
  • IP54 housing protection; electrical connections are excluded.
  • Safety class II; operating ambient temperature −20 to +60 °C.
  • Maximum rated voltage: 10 V; maximum permissible detector cable length: 3 m.
  • Maximum spectral sensitivity: approximately 540 nm.

Control Compatibility

For Siemens LMO, LMV2 and LMV3 oil burner controls in intermittent operation. LME7 and LME8 combinations are available on request. The QRB4 signal is polarity-sensitive: the black lead is positive and the blue lead is negative.

Model Comparison

QRB4A-B050B70: The QRB4A counterpart has normal sensitivity; both 50 cm versions exclude mounting fittings.

PRODUCT ENQUIRY

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Siemens QRB4 series flame detector with soft mounting plug, detail view
SiemensQRB4B-B050B70
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