EPRO PR6423/001-000 Eddy Current Sensor Probe

The EPRO PR6423/001-000 is a robust and precise eddy current sensor from the CONTREC series, specifically designed for non-contact measurement of displacement in rotating machinery. This model is a standard 8mm probe, a cornerstone of EPRO's sensing technology used in thousands of turbomachinery installations worldwide. It operates on the eddy current principle, where a high-frequency signal from a signal converter (like the CON021) energizes the probe tip, creating an alternating magnetic field. Changes in the gap between the probe tip and a conductive shaft alter the impedance of the circuit, which is then demodulated by the converter to produce a voltage proportional to displacement.

Key Features

• Industry-Standard 8mm Form Factor: The 8mm probe diameter is a common size for vibration and position monitoring, fitting a wide range of industrial mounting brackets and applications.

• Passive Sensing Element: The probe itself is a passive device containing only the coil and cable, ensuring long-term reliability and robustness.

• High-Frequency Response: Capable of measuring both static (position) and dynamic (vibration) displacements, with a frequency response suitable for most rotating machinery (typically 0-10 kHz).

• Hermetically Sealed Tip: The probe tip is hermetically sealed to protect the internal coil from contamination by oil, water, and process fluids, ensuring long service life.

• Interchangeable Calibration: PR6423 probes are designed for interchangeability, meaning a replacement probe can be installed without needing to recalibrate the entire system, minimizing downtime.

• API 670 Compliance: Meets the mechanical and electrical requirements of API 670 for non-contact vibration and position monitoring systems.

Technical Specifications

• Probe Diameter: 8 mm

• Measurement Principle: Eddy current

• Linear Range: Typically 2 mm (when used with standard EPRO converters)

• Sensitivity: 8 V/mm (nominal with 4140 steel target and EPRO converter)

• Temperature Range (Tip): -30°C to +120°C

• Cable: Integral, with options for various lengths and connectors; the /001-000 suffix denotes a specific cable and connector configuration.

• Probe Housing Material: Stainless steel

• Protection Class: IP68 (probe body) 

Applications

The PR6423/001-000 is a fundamental sensor for protecting critical rotating assets. It is used to monitor radial shaft vibration in steam and gas turbines, centrifugal and axial compressors, pumps, and generators. It also measures axial (thrust) shaft position to detect potential thrust bearing failure, and can be used for shaft eccentricity and keyphasor timing reference signals. Its robust design makes it suitable for the demanding environments of power plants, refineries, and offshore platforms.

Integration and Calibration

This probe must be used with an EPRO signal converter, such as the CON011 or CON021, which provides the necessary excitation, demodulation, and signal conditioning. The combined system is calibrated to the specific target material of the machine (usually high-strength steel like AISI 4140). The probe connects to the converter via its integral cable, often using an extension cable for convenience. The "/001-000" suffix in the model number is a crucial identifier that specifies the exact mechanical and electrical configuration, including cable length and connector type, ensuring the correct probe is used for a given installation.

Reliability and Environmental Compliance

EPRO probes are renowned for their reliability. The PR6423/001-000 is built to withstand severe vibration, shock, and temperature extremes typical of heavy industrial machinery. Its stainless steel construction and hermetic sealing provide excellent resistance to corrosion and ingress. For installations in hazardous areas, versions of the PR6423 with appropriate ATEX or IECEx certifications are available, ensuring safe operation in explosive environments.

The EPRO PR6423/001-000 is a vital component for any serious machinery protection strategy, delivering accurate and reliable data directly from the machine shaft.