Specifications Manual
  • Overview
  • Features
  • Additional Info
  • Specifications
  • Product Codes
  • Manufacturer
  • The Honeywell Triple Infrared Flame Detector FS24X is the latest generation high technology Multi-Spectrum Triple IR (IR/IR/IR/Visible) Flame Detector, which is part of our FSX family of advanced technology Electro-Optical fire detectors. Using our patented WideBand IR™, WideBand 4.3 micron IR™, and Visible detection technology, the FS24X is a quantum leap in flame detection. Sophisticated software algorithms and dual microprocessors ensure that the FS24X has the highest fire detection performance combined with optimal false alarm rejection and it does not use an external reflector for routine visual integrity checks. This exclusive technology greatly reduces faults and maintenance especially in extreme applications where salt, heavy rain, or snow are constantly present and it is especially effective in buildings or enclosures with airborne residue or dust.

    This triple infrared flame detector has dual microprocessors which provide a high level of fail-safe operation combined with fast and reliable performance. The Master Microprocessor performs high-speed digital sampling and signal-processing calculations; while the slave microprocessor handles various sensor data, performs communications, self-diagnostics and provides interface versatility; and additional memory for storing Event Log and FirePic™ data.

    The FS24X Triple Infrared Flame Detector has a detection range greater than 200 feet (Very High Sensitivity setting) for the detection of a one square-foot Heptane reference fire and has a cone of vision far greater in volumetric coverage than any other Multi-Spectrum IR Detector. This means fewer detectors can be used as compared to other manufacturers’ detectors.



  • • Optimal false alarm rejection for all environmental conditions

    • No External Reflector

    • Detects hydrocarbon and non-hydrocarbon fires

    • User selectable outputs

    • Field select sensitivity: Very high, high, medium and low

    • Minimal maintenance for trouble-free operation

    • Easy electronics module replacement

    • Test lamp available for manual testing
  • The WideBand IR™ Infrared technology using high-speed solid-state Quantum sensors allows detection of all types of fires, hydrocarbon and non-hydrocarbon, in all weather conditions. Even if the detector is required to monitor through glass, the patented WideBand IR sensors will still alarm to the presence of flame.

    The FS24X family of detectors feature our patented FirePic data storage and information retrieval facility. FirePic™ records pre-fire data, which can be recovered from the Detector’s non-volatile flash memory for post fire analysis and postulation of the fire cause. Additionally, unique Real-Time Graphing (RTG™) allows viewing of the data that the Detector actually sees. A combination of outputs makes the FS24X a truly versatile detector for today’s demanding industrial requirements.

    • Patented* WideBand IR™ Technology
    • Patented* Electronic Frequency Analysis™
    • Visible Sensor for optimum false alarm rejection
    • Selectable detection sensitivities
    • Field-of-View: 110° full 100% cone-of-vision (90° full 100% cone-of-vision model also available)
    • Dual microprocessors for reliable performance
    • Real-time clock for accurate time dating of events
    • FirePic™ — pre-fire event data storage
    • Event log with date and time stamp
    • RS-485 ModBus communication
    • Non-Isolated 4-20 mA Analog output (sink or source)
    • Alarm, Fault and Fire Verification relays
    • Automatic optical path and electronic self-test
    • Widest operating temperature range
    • Patented* Electronics Module for components protection with easy plug-in terminations and field installation
    • Two ¾” NPT OR 25mm conduit entries
    • Low power consumption
    • High RFI and EMI immunity
    • FM, ATEX, CE mark approvals
    • Meets SIL 2 requirements

  • Field of View: 90° Full 100% Cone of vision, ± 45° from on axis OR 110° Full 100%

    Sensitivity: Very High, High, Medium and Low – Switch Selectable

    Response Time: 3-5 Seconds to 1 sq. ft. n-Heptane fire at 100 ft.; 3-10 Seconds to 1 sq. ft. n-Heptane fire at 200 ft.

    Spectral Sensitivity:Visible: 400 – 700 nanometers; Near Band IR: 0.7 – 1.1 microns; Wide Band IR: 1.1 – 3 microns; Wide Band IR: 3.0 – 5.0 microns

    Operating Voltage: 24 VDC nominal (18-32 VDC) – Regulated

    Communication: Analog0 – 20 mA stepped – Source or Sink User Selectabl, Relay, & RS-485, ModBus Standard: FireBus II & HART optional

    Temperature Range: Operating: 110° Field of View FS24X: -40 to +185ºF (-40 to +85ºC); 90° Field of View FS24X: -76 to +185°F (-60 to +85°C); Storage: -67 to +230ºF (-55 to +110ºC)

    Humidity Range: 5 to 98% relative humidity, non-condensing

    Vibration: Meets or exceeds MilSpec 810C Method 514.2, Curve AW12

    Wiring: 14 AWG (2.5mm2) to 22 AWG (0.326mm2); Shielded Cable Recommended

    Conduit Entries: Standard: Two ¾” NPT or two M25

    Enclosure Materials: Copper-Free Powder Coated Aluminum or 316 Stainless Steel

    Enclosure Type: NEMA 4 & 4X, IP66

    Certifications: FM: Class I, Div. 1 & 2, Groups B, C, & D; Class II, Div. 1 & 2, Groups E, F, & G; Class III

    Shipping Weight: Aluminum: 3.6 lbs (1.6 kg); Stainless Steel: 7 lbs (3.2 kg)


  • Honeywell Analytics - FS24X-911 Series with 90° Field of View, Standard Temp Range -60° to 85°C
    Description Part Number
    QuadBand™ IR3+ detector, copper-free aluminum encl., (2) 3/4 in. NPT entries FM and ATEX approved FS24X-911-21-1
    QuadBand™ IR3+ detector, 316 stainless steel encl., (2) 3/4 in. NPT entries FM and ATEX approved FS24X-911-22-1
    QuadBand™ IR3+ detector, copper-free aluminum encl., (2) M25 entries FM and ATEX approved FM and ATEXFS24X-911-23-1
    QuadBand™ IR3+ detector, 316 stainless steel encl. (2) 25 mm entries FM and ATEX approvedFS24X-911-24-1
    Honeywell Analytics - FS24X-211 Series with 110° Field of View, Standard Temp Range -40° to 85°C
    DescriptionPart Number
    QuadBand™ IR3+ detector, copper-free aluminum encl., (2) 3/4 in. NPT entries FM and ATEX approvedFS24X-211-21-1
    QuadBand™ IR3+ detector, 316 stainless steel encl., (2) 3/4 in. NPT entries FM and ATEX approvedFS24X-211-22-1
    QuadBand™ IR3+ detector, copper-free aluminum encl., (2) M25 entries FM and ATEX approvedFS24X-211-23-1
    QuadBand™ IR3+ detector, 316 stainless steel encl. (2) M25 entries FM and ATEX approvedFS24X-211-24-1
    Honeywell Analytics - Replacement Detector Modules FS24X
    Description Part Number
    211 Series standard temp rangeFS24X-211-10
    911 Series standard temp rangeFS24X-911-10
    Honeywell Analytics - Accessories FS24X
    DescriptionPart Number
    Stainless steel swivel mounting assembly for FS24X, FS20X, FS10, SS4, SS2 detectors SM4
    Universal charger for Fire Sentry test lamps and interface kits. For 110-240 Vac with international plugs PSU-12
    IR test lamp for testing FSX detectors, explosion proof version. Incl universal charger TL-2055
    IR test lamp for testing FSX detectors, non-explosion proof version. Incl universal charger TL-1055
    Sunshield for SS2, SS4, FS20X, and FS24X detectors, 316 stainless steel SH-001
    Field of view restrictor FVR-01


  • Honeywell Analytics

    For nearly 50 years, Honeywell Analytics has been protecting people who put their lives on the line every day. It takes a special level of drive and dedication to work in hostile environments, and we believe your workers deserve the same kind of commitment from us when it comes to securing their health and safety. Right from the start, our founders were determined to find better ways to design, build and manufacture reliable gas detection solutions. Through advanced technology and pure industry know-how, Honeywell Analytics continues to improve and evolve our products. Today, we’re proud to partner with customers worldwide who share our vision of vigilance and rely on us to help them protect what matters most. From custom-designed solutions to unmatched training and support, Honeywell Analytics is simply the smartest choice when you demand the best in safety.

    Flame Detector for hydrocarbon fire and non-hydrocarbon fire – Fire Sentry FS24X – Honeywell Analytics