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SKU: 125800-01

Bently Nevada 125800-01 3500/25 Enhanced Keyphasor I/O Module

The Bently Nevada 125800-01 is an Enhanced Keyphasor I/O module with internal terminations for the 3500/25 system. It provides precise phase reference and speed measurement signals required for advanced machinery diagnostics. This USA-made module supports high-speed data synchronization and integrates seamlessly with proximity probes to protect critical turbines and compressors in demanding industrial environments.

Precision Phase Reference and Speed Measurement

The Bently Nevada 125800-01 serves as the specialized I/O interface for the 3500/25 Enhanced Keyphasor system. This module provides critical phase reference signals by tracking a “once-per-turn” event on a rotating shaft. It accepts inputs from proximity probes or magnetic pickups to determine the exact angular position of the shaft, which allows the 3500 monitoring rack to perform sophisticated vector analysis. By establishing this timing foundation, the 125800-01 enables the system to calculate synchronous vibration components (1X, 2X) and provides accurate machine speed data for turbine supervisory instrumentation.

Internal Terminations for Enhanced Reliability

Engineers optimized the 125800-01 with internal terminations to streamline installation and maximize durability. This design choice eliminates the need for external terminal blocks, reducing the number of potential failure points in high-vibration control cabinets. The module’s circuitry filters and conditions raw transducer signals, converting them into digital pulses that the 3500 backplane can process. This robust signal processing protects your data from electrical noise and transients common in industrial power plants, ensuring that the Keyphasor pulse remains crisp and reliable for diagnostic software like System 1.

Strategic Integration and Data Management

The 125800-01 resides in the 3500 rack to support advanced communication processors such as the TDI (Transient Data Interface). By occupying a dedicated slot, the module provides the essential synchronization pulse that all other vibration monitors in the rack use to align their data. This synchronization allows for the creation of Orbits, Polar plots, and Bode plots—the primary tools engineers use to diagnose machinery malfunctions like unbalance, misalignment, or shaft cracks. Its seamless compatibility with Bently Nevada’s proprietary protocols ensures efficient data exchange with your plant-wide process control system.

Essential Technical Specifications

  • Manufacturer: Bently Nevada (Baker Hughes)
  • Model Number: 125800-01
  • Module Type: Enhanced Keyphasor I/O Module
  • System Compatibility: 3500/25 Keyphasor System
  • Termination Type: Internal Terminations
  • Input Signals: Proximity Probes, Magnetic Pickups, or Optical Sensors
  • Signal Support: Up to two Keyphasor signals per module
  • Mounting: Rear of 3500 Rack (aligned with Slot 1)
  • Weight: 0.38 kg
  • Dimensions: 2.5 x 11.2 x 24.2 cm
  • Product Origin: USA

Primary Industrial Applications

  • Provides phase reference for steam and gas turbine vibration analysis.
  • Measures rotational speed for overspeed protection and status logic.
  • Synchronizes vibration data across multiple monitors in a 3500 rack.
  • Enables diagnostic “Orbit” analysis for centrifugal compressors and large pumps.