Siemens RAR9 Photocell Flame Sensor

Siemens RAR9 Photocell Flame Sensor for Yellow-Burning Oil Flames

The Siemens RAR9 is an active optical photocell flame detector engineered for continuous supervision of yellow-burning oil flames in high-capacity commercial, industrial, and marine auxiliary boilers. Operating on the photovoltaic principle within the visible light spectrum, the RAR9 utilizes a sensitive silicon element that generates a direct current (DC) signal upon illumination.

Unlike passive resistance photocells or broad-band sensors, the silicon photocell inside the RAR9 is fundamentally insensitive to infrared radiation. This design eliminates false flame confirmations caused by glowing refractory lining, incandescent combustion chamber bricks, or radiant heat after burner shutdown. Encased in an impact-resistant, dust-proof duroplast housing with protective optical glass, the RAR9 is built to withstand high vibration, ambient thermal stress (-20 °C to +60 °C), and engine room conditions.

Model Details

• Base Model (Sensor Only): RAR9 / Siemens MPN: BPZ:RAR9
• Radius Flange Assembly: RAR9(1) / Siemens MPN: BPZ:RAR9(1) (Includes clamp and radius mounting flange 4 241 8855 0)
• Straight Flange Assembly: RAR9(2) / Siemens MPN: BPZ:RAR9(2) (Includes clamp and straight mounting flange 4 241 8898 0)
• IP40 Protection Sealing Kit: AGG09 / Siemens MPN: BPZ:AGG09 (Cable gland sealing Ø 5 to 8 mm)

Technical Specifications

Key Features

1. Active Silicon Photovoltaic Element: Generates an intrinsic DC voltage signal proportional to visible flame intensity, driving control amplifiers directly.
2. Infrared Radiation Blindness: Immune to hot combustion chamber refractory and glowing firebrick reflections, preventing critical false flame-on holdovers.
3. Long-Distance Transmission Capability: Supports signal cable runs up to 100 meters without active intermediate signal conditioning.
4. Duroplast Thermal Housing: Rugged, dust-sealed thermosetting body rated for continuous operation up to +60 °C in marine boiler environments.
5. Field-Serviceable Modular Design: Removable clamp-on bayonet mounting allows rapid optical inspection, cleaning, or sensor replacement without breaking alignment.

Applications

• Marine Auxiliary & Exhaust Gas Boilers: Aalborg, KangRim, Miura, SAACKE, and Volcano marine boiler burner packages.
• Industrial Heavy Fuel Oil (HFO) & Marine Gas Oil (MGO) Burners: Monoblock and duoblock pressure-jet burners.
• Thermal Fluid Heaters & Inert Gas Generators (IGG): Marine and offshore vessel inert gas generation combustion chambers.
• Rotary Cup & Steam-Atomizing Industrial Burners: Multi-fuel firing systems operating with luminous yellow flame profiles.

Frequently Asked Questions

What is the difference between Siemens RAR9, RAR9(1), and RAR9(2)?

The core sensing element is identical across all three versions. The difference lies in the mounting accessories provided: RAR9 is the bare sensor body without clamp or mounting flange; RAR9(1) includes a mounting clamp and a radius (curved) mounting flange; RAR9(2) includes a mounting clamp and a straight mounting flange.

Can the Siemens RAR9 detect blue gas flames or clear bio-fuel flames?

No. The RAR9 is specifically tuned for yellow-burning luminous flames generated by Heavy Fuel Oil (HFO), Marine Diesel Oil (MDO), and Marine Gas Oil (MGO). For blue-burning gas flames or low-NOx burners, an ultraviolet (UV) flame detector such as the Siemens QRA2, QRA4, or QRA53/55 series must be utilized.

Does the polarity matter when wiring the RAR9 terminal strip?

The RAR9 uses a two-core terminal connection. While the internal silicon photocell produces a DC current signal, standard burner control bases (such as LAL and LOK16) designate dedicated signal input terminals (typically terminals 22/23 or designated signal pairs). Ensure connections match your specific burner control wiring schematic to maintain accurate signal amplifier circuit paths.

How do I upgrade from an older Landis & Gyr RAR7 or RAR8 to the RAR9?

The Siemens RAR9 is the direct form-fit-function replacement for legacy Landis & Gyr RAR7/8 series detectors. Mounting flange dimensions and signal characteristics with LAL/LAE control boxes are fully backwards-compatible. Ensure that the AGG09 IP40 cable sealing gland is installed if replacing in high-moisture marine engine room environments.