EPRO PR6400 Series Modules: PR6424/000-130 CON021

Technical Dossier

Product Details And Specifications

EPRO PR6400 Series: Comprehensive Module Range and Technical Overview

The EPRO PR6400 series is a family of eddy-current displacement measurement and signal conditioning modules engineered for continuous machinery protection in heavy industrial environments. Deployed extensively in petrochemical refineries, nuclear power stations, offshore platforms, and large-scale rotating machinery installations, the PR6400 series serves as the signal interface layer between proximity probes and plant-level monitoring systems such as DCS and SCADA. Its modular architecture allows integration into both legacy relay-based protection panels and modern digital control networks. The series is manufactured to IEC and API 670 standards, making it a reference-grade solution for turbine, compressor, and pump shaft monitoring applications worldwide.

The Evolution of PR6400 Architecture

The PR6400 series was introduced by EPRO (now part of Emerson Automation Solutions) as a successor to earlier eddy-current signal conditioning platforms. Early variants operated as standalone DIN-rail-mounted converters with analog 4–20 mA output, designed for direct wiring to panel meters and relay trip units. As plant automation matured through the 1990s and 2000s, EPRO expanded the PR6400 range to include versions with configurable output ranges, dual-channel capability, and compatibility with the CON0xx family of extension modules for multiplexed monitoring racks.

The CON021 extension module, as used in the PR6424/000-130 CON021, provides the physical and electrical interface between the signal converter and the monitoring rack backplane. This architecture separates the field-side signal conditioning from the system-side communication, enabling hot-swap maintenance without interrupting the monitoring loop. Later revisions introduced HART-compatible variants and digital fieldbus output options, though the core analog signal chain of the PR6400 remained the dominant deployment configuration in brownfield facilities due to its proven reliability and the high cost of full system replacement.

As of 2026, the PR6400 series is in the mature-to-end-of-life phase of its product lifecycle. EPRO/Emerson has transitioned new installations toward the PR6000 and Bently Nevada 3500 series platforms. However, the installed base of PR6400 equipment in operating plants remains substantial, and long-term maintenance support — including sourcing of discontinued modules — is a critical operational requirement for asset owners.

PR6400 Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly deployed modules within the EPRO PR6400 series, classified by functional category:

Signal Converters (Eddy-Current / Proximity)

• PR6424/000-130 CON021: Single-channel eddy-current signal converter, 4–20 mA output, CON021 rack interface, 130 mm range variant.
• PR6424/000-100 CON021: Single-channel eddy-current signal converter, 4–20 mA output, CON021 rack interface, 100 mm range variant.
• PR6424/010-130 CON021: Single-channel converter with extended cable compensation, 130 mm range, CON021 interface.
• PR6424/010-100 CON021: Single-channel converter with extended cable compensation, 100 mm range, CON021 interface.
• PR6426/000-130 CON021: Dual-channel eddy-current signal converter, 4–20 mA per channel, 130 mm range, CON021 rack interface.
• PR6426/000-100 CON021: Dual-channel eddy-current signal converter, 4–20 mA per channel, 100 mm range, CON021 rack interface.
• PR6422/000-130 CON021: Single-channel converter, voltage output variant, 130 mm range, CON021 interface.
• PR6422/000-100 CON021: Single-channel converter, voltage output variant, 100 mm range, CON021 interface.

Extension / Interface Modules (CON Series)

• CON021: Standard rack-mount extension module for PR6424/PR6426 series; provides backplane bus interface and terminal block field wiring.
• CON011: Compact extension module for single-channel PR6422 converters; DIN-rail or panel-mount compatible.
• CON041: High-density extension module supporting up to four signal converter channels on a single backplane slot.

Proximity Probe Drivers / Oscillator-Demodulators

• PR6423/000-130: Oscillator-demodulator for EPRO PR6000-compatible probes, 130 mm range, standalone DIN-rail mount.
• PR6423/000-100: Oscillator-demodulator, 100 mm range, standalone DIN-rail mount.
• PR6425/000-130: Dual-output oscillator-demodulator, 130 mm range, for redundant monitoring loops.

Power Supply Modules

• PR6427/000-000: Dedicated 24 VDC power supply module for PR6400 series monitoring racks; provides regulated, isolated power to up to eight signal converter slots.
• PR6428/000-000: Redundant power supply module for PR6400 racks; supports 1+1 redundancy configuration with automatic failover.

Sourcing Hard-to-Find & Obsolete PR6400 Parts

DriveKNMS maintains a dedicated inventory program for EPRO PR6400 series modules, including variants that have been discontinued by the original manufacturer. For operating plants that cannot justify a full migration to current-generation platforms, DriveKNMS provides the following lifecycle extension services:

• Stock of tested, pull-out PR6424, PR6426, and PR6422 converters with CON021 and CON011 interfaces.
• Cross-reference matching for superseded part numbers to identify functional equivalents within the PR6400 range.
• Emergency dispatch capability for critical plant shutdowns requiring same-day or next-day shipment.
• Long-term supply agreements for facilities with multi-year maintenance contracts requiring guaranteed module availability.

Requests for obsolete or low-volume PR6400 variants are handled directly by the DriveKNMS technical sourcing team. Provide the full part number including the CON suffix and cable compensation code when submitting inquiries.

Quality Control for the PR6400 Range

PR6400 series modules incorporate a multi-layer signal chain — probe driver oscillator, demodulation circuit, output scaling amplifier, and backplane bus interface — each of which requires independent verification before a module is released for plant service. DriveKNMS applies the following test protocol to all PR6400 units processed through its facility:

• Oscillator frequency verification: Confirms the probe driver oscillator operates within the specified frequency band (typically 1 MHz ± 5%) using a calibrated frequency counter.
• Output linearity sweep: Applies a simulated probe gap variation across the full measurement range and records the 4–20 mA output at 10% increments to verify linearity within ±0.5% of full scale.
• CON module backplane continuity test: Verifies all backplane bus pins on the CON021/CON011 interface for correct contact resistance and absence of intermittent connections.
• Isolation resistance test: Measures field-side to system-side isolation resistance at 500 VDC to confirm dielectric integrity of the signal isolation barrier.
• Thermal soak: Modules are operated at 55°C for a minimum of two hours to screen for latent thermal failures in electrolytic capacitors and voltage regulators.
• Final calibration record: Each unit is issued a test report documenting measured output values, oscillator frequency, and isolation resistance, traceable to the unit serial number.