Description
RTD Sensor with Nipple-Union-Nipple (N-U-N) Connection (Model APFS-N-U-N) is a flameproof PT100 temperature sensor designed for industrial process applications where fast maintenance, simplified servicing, and reduced process downtime are essential. Featuring a Simplex Class A PT100 sensing element, a rugged IP67 flameproof die-cast aluminium terminal head, a durable SS316 stainless steel probe, and a Nipple-Union-Nipple (N-U-N) process connection, this industrial RTD sensor delivers accurate temperature measurement across an operating range of -50°C to +400°C. Unlike conventional threaded RTD assemblies, the integrated union joint allows the sensor to be removed without repeatedly disturbing the main process connection, helping reduce thread wear, sealing maintenance, and service time.
Designed for demanding industrial environments, the APFS-N-U-N incorporates a spring-loaded nickel-plated ceramic terminal block that maintains secure electrical contact under vibration, improving wiring reliability in rotating equipment and process plants. Available with 2-wire, 3-wire, or 4-wire PT100 configurations, the sensor integrates with compatible temperature transmitters, PLCs, DCS, SCADA systems, controllers, and industrial monitoring systems. Manufactured by Aavad Instrument, this N-U-N connection RTD sensor is ideal for chemical processing, oil and gas facilities, petrochemical plants, refineries, utilities, and hazardous-area installations where frequent sensor maintenance and vibration resistance are critical operational requirements.
Additional information
| Weight |
0.3 kg |
| Dimensions |
40 × 15 × 15 cm |
| Configuration |
2 WIRE, 3 WIRE, 4 WIRE
|
Key Features
-
Service-Friendly 150mm N-U-N Connection Mechanical union allows swift extraction of the sensor element for validation without unthreading or stressing the pipe-side process tapping.
-
Vibration-Resistant Spring-Loaded Terminals Upgraded nickel-plated ceramic terminal blocks maintain constant contact pressure under severe, high-frequency equipment vibration.
-
Certified Flameproof IP67 Protection Ruggedized, explosion-proof terminal housing provides absolute security against gas ignition, dust, and heavy outdoor weather.
-
High-Precision Class A Compliance Delivers elite calibration accuracy ($pm0.15^circtext{C}$ at $0^circtext{C}$) to guarantee exceptionally tight, linear thermal tracking loops.
-
Versatile 2, 3, or 4-Wire Wiring Configurations Flexible internal engineering adapts easily to basic indicator loops or high-precision 4-wire lead-resistance compensation setups.
-
Durable Marine-Grade SS316 Core Metallurgy Stainless steel probe housing resists high-temperature scale build-up, surface oxidation, and aggressive chemical erosion.
-
Extended Service Lifecycle Engineering Prevents localized leak paths and structural pipe-wall failure caused by repeated metal thread tightening cycles.
-
Broad Mechanical System Compatibility The ultimate choice for tracking temperature on heavy rotating machinery, turbulent piping loops, and isolated process skids.
Applications
-
High-Vibration Machinery Monitoring Continuous thermal defense on heavy reciprocating pumps, multi-stage compressors, and industrial milling gearboxes.
-
Volatile Petrochemical Gas Transfer Lines Safe, flameproof temperature tracking across pressurized natural gas headers and hydrocarbon transport networks.
-
High-Frequency Maintenance Processing Loops Ideal for batch reactor lines and mixing tanks that require aggressive, frequent calibration pulling cycles.
-
Refinery and Distillation Unit Infrastructure Reliable, long-term monitoring inside dangerous, highly classified process zones demanding low piping maintenance downtime.
Datasheet
FAQs
1. What is a Nipple-Union-Nipple (N-U-N) Connection on an RTD Sensor?
A Nipple-Union-Nipple (N-U-N) connection is a mechanical process connection that uses a union joint between two threaded nipples, allowing the PT100 RTD Sensor to be removed for calibration, maintenance, or replacement without disturbing the main process connection. This design reduces thread wear, maintenance time, and sealing issues during repeated servicing.
2. What are the specifications of Aavad’s N-U-N RTD Sensor?
Aavad’s Model APFS-N-U-N is a simplex PT100 RTD Sensor with Class A accuracy and an operating temperature range of -50°C to +400°C. It features a 150 mm SS316 Nipple-Union-Nipple (N-U-N) connection, a 6 mm outer diameter (OD) SS316 sheath, and a die-cast aluminum flameproof protection head rated IP67 for hazardous industrial environments.
3. What is a Spring-Loaded Terminal Block and why does this Sensor use one?
A spring-loaded nickel-plated ceramic terminal block maintains constant contact pressure between the electrical wiring and the PT100 sensing element, even under vibration and thermal expansion. This improves electrical reliability and measurement stability, making the sensor suitable for pumps, compressors, gearboxes, turbines, and other rotating equipment.
4. Can this Sensor be configured for different wiring standards?
Yes. Aavad Instrument manufactures this PT100 RTD Sensor in 2-wire, 3-wire, and 4-wire configurations, allowing seamless integration with temperature transmitters, PLCs, DCS systems, SCADA platforms, and industrial process controllers across different plant wiring standards.
5. Where is the N-U-N Connection RTD Sensor typically used?
N-U-N Connection RTD Sensors are widely used in high-vibration pumps, multi-stage compressors, gearboxes, petrochemical pipelines, refineries, distillation units, batch reactors, mixing tanks, chemical processing plants, and industrial process systems where frequent sensor removal, simplified maintenance, and reliable temperature measurement are important.
