HTS KS – Flame Detector Unit (FDU 510 / FDU 520)

Overview

The Honeywell Kromschröder® Flame Detector Unit (FDU) series provides OEMs, burner manufacturers, and end users with a state-of-the-art flame monitoring solution for gas burners across a wide range of industrial applications. Replacing the Kromschröder IFW 15/50, R4343, and BC1000 flame relay models, the FDU series enables multi-flame control and multi-point monitoring in conjunction with burner control units (BCUs) such as the Kromschröder BCU 560 or a failsafe PLC with a standard-compliant flame monitoring device.

Two models are available: the FDU 510 for gas burners in intermittent operation (applications under 24 hours) and the FDU 520 for gas burners in continuous operation (applications exceeding 24 hours). The compact DIN-rail-mounted design allows easy integration into control cabinets alongside other equipment, providing convenient access for maintenance and repair. Configuration and diagnostics are handled via the BCSoft software tool on a Windows PC.

Features & Benefits

• Two dedicated models for distinct duty cycles — FDU 510 for intermittent burner operation and FDU 520 for continuous operation, ensuring the correct safety integrity for each application type.
• Multi-sensor flame detection compatibility — Accepts UV sensors, ionization probes, UVC sensors, and C70xx photocell series, providing flexibility across burner configurations.
• Adjustable Flame Failure Detection Time (FFDT) — Selectable at 0.7, 1.7, 2.7, or 3.7 seconds to match system safety requirements.
• Analog flame signal output — 0 to 5 V analog output provides continuous flame intensity monitoring for diagnostics and process visibility.
• Fieldbus communication via BCM 500 module — Optional PROFINET and Modbus TCP connectivity for integration into modern plant control systems.
• BCSoft PC configuration software — Class C double-channel architecture with comparison enables precise setup and diagnostics from a Windows PC.
• Compact DIN-rail mounting — 60 x 115 x 112 mm footprint fits standard 35 x 7.5 mm DIN rail; ideal for cabinet-integrated installations.
• Broad international approvals — Certified to EN 298, EN 746-2, UL (USA/Canada), FM, CE, GAR, and NFPA 86 for global deployment.
• SIL-rated safety — FDU 520 carries SIL certification per DIN EN 61508 for safety-critical applications.
• Replaces legacy Kromschröder flame relays — Direct upgrade path from IFW 15/50, R4343, and BC1000 platforms.

Technical Specifications

• Models: FDU 510 (intermittent operation), FDU 520 (continuous operation)
• Supply Voltage: 120 VAC (FDU..Q), 230 VAC (FDU..W), ±15%
• Power Consumption: < 10 VA
• Flame Control Types: UV sensor, ionization, UVC, C70xx series
• Flame Signal Range: 1–15 μA (C70xx); 1–25 μA (ionization / UVS / UVC)
• Analog Output: 0 to 5 V (flame signal intensity)
• Flame Failure Detection Time (FFDT): Adjustable — 0.7 / 1.7 / 2.7 / 3.7 seconds
• Contact Ratings: 2 A (SIL 3: max. 0.1 A)
• Connection: Screw terminals (2.5 mm²), spring terminals (1.5 mm²)
• Fieldbus Communication: PROFINET, Modbus TCP (via BCM 500 module)
• Software Tool: BCSoft (Windows PC) — Software Class C, double-channel architecture with comparison
• Mounting: DIN rail 35 × 7.5 mm
• Dimensions: 60 mm W × 115 mm H × 112 mm D
• Enclosure Rating: IP20 (device); IP54 required for installation (e.g., control cabinet)
• Ambient Temperature: -20 to +60 °C (-4 to +140 °F)
• Storage Temperature: -20 to +80 °C (-4 to +176 °F)
• Relative Humidity: 5 to 95% RH, non-condensing
• Maximum Operating Cycles: 250,000
• Burner Type: Gas burners with or without fan
• Approvals: EN 298, EN 746-2, LVD, EMC, GAR, UL (USA/Canada), FM, CE, NFPA 86, EN 60730-1; FDU 520 also: SIL (DIN EN 61508), AGA, UKCA

Applications

• Gas-fired industrial burners — intermittent and continuous duty
• Hot-air furnaces and dryers
• Gas-fired boilers
• Industrial furnaces and kilns
• Excess-gas flaring installations
• Multi-burner systems requiring multi-flame control or multi-point monitoring
• OEM burner packages and skid-mounted combustion systems

Models / Configurations

• FDU 510 – Flame detector unit for gas burners in intermittent operation (less than 24 hours); available in 120 VAC (FDU 510Q) and 230 VAC (FDU 510W) versions
• FDU 520 – Flame detector unit for gas burners in continuous operation (more than 24 hours); SIL-rated per DIN EN 61508; available in 120 VAC (FDU 520Q) and 230 VAC (FDU 520W) versions

Honeywell Kromschröder FDU Accessories

• BCM 500 – Communication module adding PROFINET and Modbus TCP fieldbus connectivity to FDU 510 and FDU 520 units
• BCSoft V 4.0.0 – Windows PC software for configuration, parameterization, and diagnostics of FDU series units
• BCU 560 – Kromschröder Burner Control Unit compatible for use in conjunction with FDU series for multi-burner flame control applications

Documentation