Description
Compact Flameproof RTD Sensor (Model APFD-45×45) is an ultra-short duplex PT100 temperature sensor specifically engineered for hazardous-area installations where conventional RTD probes cannot be accommodated due to restricted installation space. With an overall probe length of only 45 mm, this compact industrial RTD is ideal for shallow thermowells, compact process nozzles, skid-mounted equipment, miniature reactors, and process vessels requiring minimal insertion depth. The sensor combines dual Class A PT100 sensing elements (3+3 wire) with an IP67 flameproof die-cast aluminium terminal head, providing two independent temperature signals for process control, safety systems, or redundant monitoring while maintaining reliable operation across -50°C to +400°C.
Unlike standard flameproof RTD assemblies that prioritize deeper immersion, the APFD-45×45 is optimized for space-constrained hazardous-area applications where installation clearance is the primary design limitation. Its double cable entry simplifies separate wiring for independent instrumentation circuits, while optional terminal head materials including cast iron, SS304, and SS316 allow selection according to environmental requirements. Standard configurations are suitable for Gas Groups I, IIA, and IIB, with IIC-rated assemblies available on request, according to the provided specifications. Manufactured by Aavad Instrument, this compact flameproof RTD integrates seamlessly with compatible temperature transmitters, PLCs, DCS, SCADA systems, safety controllers, and industrial automation platforms used across oil & gas, petrochemical, chemical, pharmaceutical, and energy industries.
Key Features
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Ultra-Short 45 mm Probe Footprint The shortest flameproof sensor in the lineup, purposely built to fit low-clearance nozzles and shallow processing lines.
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Duplex Dual-Circuit Architecture Houses two independent 3-wire Pt100 elements to simultaneously supply automation loops and separate emergency trip networks.
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Double Cable Entry Conduit Ports Twin wiring entries allow independent signal lines to exit the flameproof head without needing external splitter junction boxes.
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Stepped Sheath Engineering Profile Features a rapid-response 8 mm OD tip that broadens into a high-strength 12 mm neck for a balance of speed and ruggedness.
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Certified Flameproof IP67 Protection Ruggedized, explosion-proof terminal housing provides absolute security against gas ignition, dust, and high-pressure water spray.
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Broad Hazardous Gas Certifications Rated for safe, dependable operation across industrial Gas Groups I, IIA, and IIB out of the box.
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High-Precision Class A Compliance Adheres to strict international calibration limits ($pm0.15^circtext{C}$ at $0^circtext{C}$) to guarantee tight, dependable thermal loops.
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Adaptive Enclosure Material Options Available with upgraded cast iron, SS304, or marine-grade SS316 terminal heads to match aggressive facility wash-down chemicals.
Applications
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Compact Chemical Skid Assemblies Inline temperature profiling inside tight, pre-assembled modular dosing skids and specialized mixing modules.
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Shallow Processing Pipes and Vessels Reliable center-stream monitoring within small-diameter pipelines and low-volume storage tanks in classified areas.
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Oil & Gas Extraction Facilities Safe thermal monitoring near extraction manifolds, hydraulic pumps, and distribution blocks with limited mounting room.
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Hydrogen-Adjacent Processing Zones Upgradable to IIC configurations for high-risk hydrogen gas production, fuel cell testing, and storage facilities.
Datasheet
FAQs
1. What makes the Compact Flameproof RTD Sensor different from a Standard Flameproof RTD?
The Compact Flameproof RTD Sensor is specifically designed for space-constrained industrial applications. Aavad’s Model APFD-45×45 features an overall probe length of just 45 mm, making it ideal for shallow thermowells, compact process nozzles, skid-mounted equipment, and other installations where conventional flameproof RTD sensors cannot be accommodated.
2. What are the specifications of the Compact Flameproof RTD Sensor?
This model is a duplex (3-wire + 3-wire) PT100 RTD Sensor with Class A accuracy and an operating temperature range of -50°C to +400°C. It features an 8 mm tip outer diameter (OD) stepping up to a 12 mm neck, along with a die-cast aluminum flameproof protection head rated IP67 and double cable entry for reliable hazardous-area operation.
3. What hazardous gas certifications does this Compact Sensor support?
Standard configurations are suitable for Gas Groups I, IIA, and IIB, with Gas Group IIC (Hydrogen) assemblies available on request, subject to applicable certification. This makes the sensor suitable for oil & gas facilities, chemical plants, petrochemical industries, hydrogen processing, fuel cell testing facilities, and other classified hazardous areas.
4. Why does this Sensor use Double Cable Entry instead of Single?
The double cable entry allows the two independent PT100 sensing elements in the duplex RTD to be wired separately. This enables one element to connect to the primary automation system (PLC/DCS/SCADA) while the second can be used for backup monitoring, safety interlocks, alarms, or trip circuits without requiring an external junction box.
5. Where is the Compact Flameproof RTD Sensor typically used?
Compact Flameproof RTD Sensors are widely used in compact chemical skid assemblies, shallow process pipelines, pressure vessels, oil & gas extraction facilities, petrochemical plants, hydrogen processing systems, fuel cell testing equipment, and other hazardous industrial applications where limited installation space and explosion-proof protection are essential.
