Bently Nevada 81034-01 Keyphasor Input Module

The 81034-01 Keyphasor input module from Bently Nevada captures once-per-turn reference signals inside turbine and rotating machinery protection systems. Plant engineers install this module whenever speed, phase, and vibration data need a precise shaft reference. Consequently, it keeps measurement channels synchronized with actual rotor position.

Key Technical Specifications

The table below outlines the main physical and electrical parameters of the 81034-01 module.

Parameter	Specification
Product Type	Keyphasor Input Module
Compatibility	Bently Nevada 3300 / 3500 series systems
Dimensions	Approximately 254 mm x 127 mm x 51 mm
Weight	Approximately 1.0 kg (2.2 lbs)
Mounting	Rack frame or panel mounting base
Interface	Backplane bus and transducer input terminals
Connectors	Multi-pin connector and terminal blocks
Component Count	Multiple signal processors, drivers, and logic circuits
Energy Storage	On-board capacitors for signal and voltage stabilization
Input Channels	Keyphasor reference signal input
Signal Type	Once-per-turn pulse from proximity probe
Operating Temperature	0 degrees C to 60 degrees C
Storage Temperature	-40 degrees C to 85 degrees C
Humidity	5% to 95% non-condensing

Functional Overview

This module reads once-per-turn pulses and converts them into shaft reference data. Therefore, it supplies phase and speed information to vibration and position monitors. The 81034-01 also synchronizes measurement channels so that data aligns with rotor angle. Meanwhile, its onboard energy storage stabilizes signals against transient electrical noise.

Installation and Handling Notes

Always verify probe gap voltage before connecting transducers to the 81034-01. In addition, route signal cable away from power wiring to reduce interference. Tighten terminal screws evenly to prevent intermittent connections. Finally, confirm pulse detection during commissioning.