EPRO PR6423/000-131 Eddy Current Proximity Sensor

The Emerson PR6423/000-131, also cataloged as the PR6423 Proximity Sensor, operates as a dedicated hardware component for non-contact shaft vibration and displacement measurement within turbomachinery monitoring systems.

Hardware Specifications

Eddy-Current Scaling and Gap Voltage Validation

The PR6423 utilizes high-frequency eddy-current impedance sensing to evaluate target surface movement without mechanical contact. High-frequency electromagnetic excitation generates localized eddy currents within the 42CrMo4 ferromagnetic steel shaft, modulating the sensor coil inductance as shaft position shifts. The secondary converter processes this modulation into a linear signal defined by the nominal 8 V/mm (~203.2 mV/mil) sensitivity curve across a 0-10 kHz (-3 dB) bandwidth. Verification of static gap voltage at the ~1.0 mm nominal air gap ensures target positioning resides centered within the dynamic linear operational envelope, suppressing high-frequency cross-talk interference from surrounding metallic structures.

Frequently Asked Questions

Q: What converter interfaces can process the raw output of the PR6423/000-131?

A: The passive sensor pairs with EPRO signal converters including the CON011, CON021, CON031, and CON041 series, which condition the coil impedance variation into standard voltage outputs for AMS 3000 machinery protection hardware.

Q: Is the PR6423/000-131 suitable for high-speed turbine shaft monitoring?

A: Yes. The sensor maintains dynamic frequency response up to 10 kHz (-3 dB) and supports target shaft surface tangential speeds up to 2,500 m/s (~98,425 ips) without signal degradation.

Field Installation Guidelines

• Sensor Mounting and Target Alignment: Thread the stainless steel sensor body into the rigid mounting bracket, maintaining perpendicularity to the shaft centerline. Adjust probe depth to establish the ~1.0 mm nominal air gap relative to the 42CrMo4 steel target surface before torquing the jam nut.
• Armored Cable Cable Routing: Route the flexible armored cable along grounded cable trays away from high-voltage conduit runs and variable frequency drive (VFD) output cables to minimize electromagnetic signal distortion.
• Grounding and Shielding: Connect signal cable shields exclusively at the converter terminal block end to establish single-point ground loop prevention. Ensure the sensor shell bonds directly to machine ground through the physical mounting thread engagement.