1. Description:
The Honeywell 2104B2131 is specifically the Receiver Unit for the Honeywell Searchline Excel Infrared (IR) Open Path Flammable Gas Detector, designed for Medium Range applications (40 to 120 meters / 130 to 390 feet). It is a critical component of a system that provides continuous, non-contact detection of combustible hydrocarbon gases (such as methane, ethane, propane, etc.) over a wide, extended area. The Searchline Excel system operates with a transmitter (e.g., 2104B2081) that emits an infrared beam, and the receiver (2104B2131) detects this beam. When flammable gas is present in the path, it absorbs specific IR wavelengths, and the receiver measures this absorption to determine the gas concentration over the entire path. The 2104B2131 is built with a robust 316 stainless steel housing and is engineered for high immunity to environmental interferences like fog, rain, and direct sunlight. This particular model is an “ATEX Source” variant, meaning it provides the 4-20mA output as a current source.
2. Application Scenarios:
Consider a large refinery where multiple processing units, pipe racks, and storage tanks are spread across an expansive area. The potential for large, dispersed flammable gas clouds from leaks in pipelines or equipment is a constant risk. Traditional point detectors might be too numerous and costly to provide comprehensive coverage for such a wide area, and their individual detection zones could miss large, drifting plumes. The Honeywell 2104B2131 Searchline Excel Medium Range Receiver (paired with its compatible transmitter) would be strategically deployed to cover these extended zones. Pairs of transmitter-receiver units would create long, continuous detection paths across critical sections of the refinery. If a gas leak occurs and a cloud forms and drifts into the path of an IR beam, the system immediately detects the presence and concentration of the flammable gas across that entire medium-range segment (up to 120 meters). This provides rapid, wide-area detection, indicating the size and approximate location of the hazard. This directly addresses the pain points of inadequate coverage, slow response times, and high installation costs associated with traditional point detectors in large, open-air industrial settings, significantly enhancing site safety and emergency response capabilities.
3. Parameter:
Main Parameters Value/Description Product Model: Honeywell 2104B2131 Manufacturer: Honeywell Analytics (part of Honeywell) Product Category: Open Path Infrared Flammable Gas Detector – Receiver Unit Associated Product: Honeywell Searchline Excel Open Path Gas Detector System Function: Detects infrared beam from the transmitter and measures gas absorption Gas Types Detected: Hydrocarbons (Methane, Ethane, Propane, Butane, Pentane, Ethylene, Propylene, Butadiene, Ethanol, Methanol) Detection Range: 0 to 5 LEL.m (Lower Explosive Limit per meter) Path Length (Medium Range): 40 to 120 meters (130 to 390 feet) Light Source (from transmitter): Xenon flash lamp Output Signal: 4-20mA analog output (current source) and/or Modbus RS485 (via termination unit) Supply Voltage: 18V to 32V DC, 8W maximum consumption Response Speed (T90): Less than 3 seconds (under normal operating conditions) Operating Temperature: -40°C to +65°C (-40°F to 150°F) Operating Humidity: 0 to 99% RH (non-condensing) Housing Material: 316 Stainless Steel Ingress Protection: IP66 and IP67 Approvals: ATEX, IECEx, UL, FM/CSA, SAA, GOSST (for hazardous areas and performance) Immunity: 100% immune to sunlight and other radiation sources (flare stacks, arc welding, lightning) Features: Contamination resistant optics, integral functional gas test facility, advanced diagnostics (window clarity, alignment accuracy).
4. Technical Principles and Innovative Values:
The Honeywell 2104B2131 Searchline Excel Medium Range Receiver embodies sophisticated technical principles and offers significant innovative value, particularly for its extended range:
- Innovation Point 1: Patented Dual-Beam Infrared Absorption for Extended Paths: The receiver is engineered to precisely detect two distinct infrared wavelengths emitted by the transmitter across the extended 120-meter path: a measurement wavelength absorbed by the target gas and a reference wavelength that is not. Its advanced digital signal processing accurately compares these received signals to compensate for environmental interferences (like fog, rain, or dust) over longer distances, ensuring highly specific and quantitative detection of gas concentrations across the entire, expansive path.
- Innovation Point 2: Robust Optical Design for Long-Range Solar Immunity: A key innovation for medium-range applications is the optimized optical design of the receiver, coupled with the high-intensity Xenon flash lamp of the transmitter. This combination ensures the system’s unparalleled 100% immunity to direct sunlight and other strong IR sources over the extended path. The receiver’s specialized detectors are precisely tuned to the pulsed and shaped infrared output of the transmitter, effectively filtering out extraneous signals and guaranteeing reliable and continuous gas detection even in challenging outdoor conditions.
- Innovation Point 3: Wide Area Coverage with Quantitative Measurement and Advanced Diagnostics: The Searchline Excel system, with the 2104B2131 receiver, provides continuous, wide-area volumetric detection (0-5 LEL.m) for medium-range applications. This quantitative measurement of gas concentration over a large area (LEL.m) offers a more comprehensive understanding of the gas cloud’s size and potential hazard than point detectors. Furthermore, the receiver incorporates advanced diagnostics, continuously monitoring window clarity and alignment accuracy, to maximize system uptime and ensure the system is always operating optimally with no unrevealed failures.
5. Application Cases and Industry Value:
In a vast petrochemical complex, extensive pipe racks and processing areas require comprehensive flammable gas monitoring. Point detectors would be impractical due to the sheer size and dispersed nature of potential leak sources. By strategically deploying multiple pairs of Honeywell 2104B2131 Searchline Excel Medium Range Receivers and their corresponding transmitters along critical pathways and across open processing zones, the complex established an advanced, wide-area detection network. These open-path detectors continuously monitored for hydrocarbon leaks over path lengths up to 120 meters. Upon detection of a gas cloud, the system would immediately alert the central control room, providing a crucial early warning. This allowed operators to quickly identify the affected area, assess the magnitude of the leak (based on LEL.m readings), and implement emergency response procedures like shutting off valves or evacuating personnel long before a dangerous concentration accumulated at a single point. This enhanced early warning capability significantly improved overall safety, reduced the risk of large-scale incidents, and protected valuable assets and personnel within the complex.
6. Related Product Combination Solutions:
The Honeywell 2104B2131 is an indispensable part of the Honeywell Searchline Excel Open Path Gas Detection system:
- Honeywell Searchline Excel Transmitter Unit (e.g., 2104B2081 for Medium Range): This unit is mounted opposite the 2104B2131 receiver and emits the infrared beam.
- Honeywell Searchline Excel Termination Unit (e.g., DX100, DVC100): This unit provides field wiring connections, power distribution, and converts the internal signal from the receiver into an industry-standard 4-20mA analog output and/or Modbus RS485 digital output for integration with a plant’s Distributed Control System (DCS) or PLC.
- Handheld Interrogator (e.g., 2104N2999): A portable tool used for commissioning, alignment, calibration, and maintenance of the Searchline Excel system, connecting directly to the receiver.
- Mounting Brackets and Alignment Kits (e.g., 02104-N-4007): Essential accessories for proper mechanical installation and precise optical alignment of both the transmitter and receiver units, particularly critical for medium-range paths.
- Calibration Gas and Gassing Cells/Test Filters: Used to perform functional gas tests and calibrate the system periodically, ensuring accuracy and compliance.
- DCS/PLC System: Receives the 4-20mA or Modbus data from the Searchline Excel system for alarm management, data logging, and integration into the plant’s safety instrumented system (SIS).
