PR6422 Eddy Current Proximity Probe (Industrial-Grade 5mm Sensor)

Precision non-contact displacement measurement starts with the right sensor. The PR6422 eddy current proximity probe (part number 012-050-RAD) delivers industrial-grade performance for turbomachinery vibration monitoring, shaft position tracking, and rotating equipment diagnostics. With its compact 5mm sensing diameter and 16 V/mm output sensitivity, this probe transforms mechanical motion into actionable electrical signals—enabling predictive maintenance strategies that prevent costly downtime.

Designed for reliability in extreme environments, the PR6422 operates continuously from -40°C to +125°C while maintaining measurement accuracy within ±1% of full scale. Whether you're monitoring steam turbine shaft runout, tracking compressor rotor position, or analyzing pump bearing clearances, this sensor provides the data foundation for condition-based maintenance programs across power generation, oil & gas, and process industries.

The stainless steel construction and integral armored cable ensure long-term durability in corrosive atmospheres, high-vibration installations, and chemically aggressive environments where standard sensors fail prematurely.

Key Performance Advantages

→ Non-Contact Operation Eliminates Mechanical Wear
Unlike contact-based sensors that degrade over time, eddy current technology measures displacement through electromagnetic induction—no physical contact with the rotating shaft means zero friction, no wear parts, and maintenance-free operation for years of continuous service.

→ 10 kHz Frequency Response Captures Dynamic Events
With bandwidth extending to 10,000 Hz, the PR6422 detects both slow-roll imbalance (sub-Hz) and high-frequency bearing defects (kHz range) in a single measurement channel. This wide frequency response eliminates the need for multiple sensor types in comprehensive vibration analysis systems.

→ Compact 5mm Diameter Fits Tight Installations
The miniaturized sensing tip accesses confined spaces on small-diameter shafts, compact bearing housings, and retrofitted machinery where larger 8mm or 11mm probes cannot physically install. M12 x 1.0mm mounting threads provide secure attachment in standard probe holders.

→ Armored Cable Withstands Harsh Environments
Integral stainless steel cable armor protects against mechanical impact, electromagnetic interference, and chemical exposure. The radial cable exit (RAD configuration) simplifies routing in crowded machinery compartments while maintaining bend radius specifications.

→ Extended Temperature Range Supports Extreme Applications
From cryogenic LNG pumps (-40°C) to high-temperature steam turbines (+125°C), the PR6422 maintains calibration accuracy without temperature compensation circuits. This thermal stability reduces installation complexity and eliminates seasonal recalibration requirements.

→ Linear Output Simplifies Signal Processing
The proportional voltage output (16 V/mm sensitivity) provides direct displacement-to-voltage conversion across the 0-1.0mm measurement range. When paired with CON041 or CON021 signal converters, the system delivers industry-standard 4-20mA or ±10V outputs compatible with any DCS, PLC, or SCADA platform.

Industrial Application Solutions

Power Generation Turbomachinery
In steam turbines, gas turbines, and combined-cycle plants, the PR6422 monitors shaft radial vibration and axial position to detect bearing wear, rotor bow, and thermal growth. Continuous monitoring enables operators to identify developing faults weeks before catastrophic failure, scheduling maintenance during planned outages rather than emergency shutdowns. The sensor's high-temperature capability makes it ideal for turbine bearing pedestals where ambient temperatures exceed 100°C.

Petrochemical Rotating Equipment
Centrifugal compressors, pipeline pumps, and process blowers in refineries and chemical plants operate under demanding conditions—high pressures, corrosive fluids, and continuous duty cycles. The PR6422's stainless steel construction resists H2S, chlorine, and acidic vapors while providing the measurement accuracy required for API 670 machinery protection systems. Installation in hazardous area Zone 2 locations is supported when paired with intrinsically safe signal converters.

Industrial Motor & Gearbox Monitoring
Electric motors driving critical processes—fans, conveyors, mixers, extruders—benefit from continuous shaft position monitoring that detects misalignment, soft foot conditions, and bearing degradation. The PR6422's compact size allows retrofitting onto existing motor frames without major modifications. Gearbox applications use multiple probes to measure gear mesh quality, pinion runout, and housing vibration for comprehensive drivetrain health assessment.

Hydroelectric & Wind Turbine Systems
Renewable energy installations demand sensors that survive moisture, temperature cycling, and years of unattended operation. The PR6422's hermetically sealed construction and corrosion-resistant materials ensure reliable performance in hydroelectric generator thrust bearings and wind turbine main shaft assemblies. Remote monitoring integration enables condition assessment without site visits to offshore or mountain installations.

Technical Specifications & Selection Guide

Selection Criteria: Choose the PR6422 5mm probe when shaft diameter is less than 50mm, installation space is limited, or existing machinery has 5mm probe mounting provisions. For larger shafts (>100mm diameter) or applications requiring extended measurement range (>1.5mm), consider the PR6423 8mm or PR6424 11mm sensor variants. Always verify target material composition—ferrous metals provide optimal sensitivity, while aluminum or titanium shafts may require sensitivity adjustment or alternative sensor technologies.

Advanced Integration & Customization

Signal Conditioning Options: The PR6422 raw output requires an Emerson EPRO signal converter to provide excitation voltage and linearize the impedance-based signal. The CON041 series offers single-channel conversion with 4-20mA output for simple PLC integration, while the CON021 multi-channel rack systems support up to 16 probes in centralized monitoring architectures. Both converter families include adjustable gap voltage settings, OK/Alert relay outputs, and HART communication for remote diagnostics.

Wireless Monitoring Solutions: For retrofit applications where cable installation is cost-prohibitive, pair the PR6422 with wireless vibration transmitters that convert the analog signal to digital data packets transmitted via ISA100, WirelessHART, or LoRaWAN protocols. Battery-powered nodes enable monitoring in rotating equipment located in remote areas without AC power infrastructure.

Predictive Analytics Integration: Modern condition monitoring platforms ingest PR6422 vibration data into cloud-based analytics engines that apply machine learning algorithms to detect anomalies, predict remaining useful life, and recommend maintenance actions. Integration with enterprise asset management (EAM) systems automates work order generation when vibration thresholds are exceeded.

Delivery, Warranty & Technical Support

Lead Time: Standard stock items ship within 2-3 business days. Custom cable lengths or special configurations require 3-4 weeks manufacturing lead time. Expedited shipping available for emergency replacements.

Warranty Coverage: 24-month manufacturer warranty covers defects in materials and workmanship. Extended warranty programs available for critical applications requiring guaranteed uptime.

Technical Assistance: Application engineering support includes sensor selection guidance, installation drawings, calibration procedures, and troubleshooting assistance. Field service available for commissioning and on-site training.

Documentation Package: Each sensor ships with calibration certificate (NIST-traceable), installation manual, dimensional drawings, and wiring diagrams. Digital documentation library includes 3D CAD models (STEP format) and product datasheets.

Frequently Asked Questions

What signal converter is required for the PR6422 sensor?
The PR6422 requires an Emerson EPRO CON041 or CON021 series signal converter to provide excitation voltage and convert the raw impedance signal into a calibrated 4-20mA or ±10V output. The converter also supplies power to the sensor and performs linearization of the displacement-to-voltage relationship.

Can this probe measure non-ferrous materials like aluminum or stainless steel?
Eddy current sensors work best with ferrous (magnetic) materials like carbon steel or cast iron. Non-ferrous targets (aluminum, brass, stainless steel) can be measured but require recalibration and may exhibit reduced sensitivity. For non-ferrous applications, consult factory application engineering for target-specific calibration data.

What is the minimum shaft diameter for reliable measurement?
The 5mm probe tip requires a minimum shaft diameter of 25mm to avoid edge effects and maintain measurement accuracy. For smaller shafts, the sensor may still function but linearity and sensitivity will be compromised. Shafts below 20mm diameter should use specialized small-diameter probes.

How do I set the correct probe-to-shaft gap distance?
The optimal operating point is typically 0.5-1.0mm gap (mid-range of the 0-1.0mm linear range). This provides equal measurement capability for shaft movement toward and away from the probe. Use precision feeler gauges or gap-setting tools during installation, then verify the gap voltage output matches the calibration curve provided with the sensor.

Is the armored cable field-replaceable if damaged?
No, the PR6422 features an integral cable permanently attached to the sensor body. Cable damage requires complete sensor replacement. To protect against cable failure, route the armored cable through conduit or cable trays, maintain minimum bend radius (10x cable diameter), and avoid sharp edges or pinch points.

Can multiple PR6422 sensors share a single signal converter?
No, each PR6422 sensor requires a dedicated signal converter channel. The CON021 multi-channel rack systems provide up to 16 independent converter channels in a single chassis, reducing panel space and simplifying wiring compared to individual CON041 modules.

Order Your PR6422 Proximity Probe Today

Ensure your critical rotating equipment operates reliably with proven eddy current sensing technology. Contact our technical sales team for application-specific recommendations, volume pricing, or integration support. We provide global shipping with full export documentation and customs support.

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