Product Overview

• PN: 3500/50M, Part No: 286566-02
• Brand: Bently Nevada (Baker Hughes)
• Series: 3500 Turbomachinery Protection TSI System
• Type: Tachometer & Keyphasor Monitoring Front Module

• Function: Core speed acquisition unit for the 3500 rack system, equipped with two independent signal input channels. It receives pulse feedback from 3300XL eddy current probes and magnetic pickup sensors, calculates real-time rotational speed, startup acceleration and rotation direction. It supports zero-speed standby alarm, overspeed protection and reverse rotation interlock, and transmits standardized keyphasor timing signal to the rack backplane to provide phase reference for all vibration monitoring channels. Measured data and alarm status are uploaded to communication modules, with hardwired relay trip output independent of upper network communication

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Core Features

• Two fully isolated input channels, available for dual redundant speed sampling or dual shaft speed detection
• Built-in peak value locking function to record maximum rotating speed and reverse rotation times for fault tracing
• Front panel indicator lamps display module operating status, channel signal validity and alarm triggers
• Complete self-diagnosis to detect sensor disconnection, short circuit and abnormal signal faults
• Hot swappable under redundant rack power supply without shutting down the entire cabinet
• Onboard circuit distributes keyphase signal to backplane, eliminating need for separate dedicated keyphasor card
• Multiple programmable alarm modes including overspeed, speed band, zero speed and acceleration deviation

• Matches dedicated rear I/O terminal board for on-site field wiring termination

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Technical Specifications

• Typical Power Consumption: 5.8 W
• Effective Speed Measurement Range: 0.1 ~ 60000 RPM
• Input Signal Type: Proximity probe signal, magnetic pickup pulse signal
• Operating Temperature: -40℃ ~ +85℃
• Overall Dimension: 241.3 × 24.4 × 241.8 mm
• Net Weight: 0.82 kg
• HS Code: 8538900000
• Certifications: CE, UL

• Product Status: OEM discontinued; brand new original sealed and fully inspected refurbished modules in stock

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Compatibility

• Matching Rear I/O Board: 133442-01 internal termination rear terminal module
• Applicable Chassis: All 3500/05 12-slot and 14-slot standard rack frames
• Supported Sensors: Full range 3300XL proximity probes, passive magnetic speed pickups
• Compatible Software: Official 3500 rack configuration tool, Bently Nevada System 1 predictive maintenance platform

• Cooperative Modules: Works with 3500/42M vibration monitor to complete phase-locked vibration analysis

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Application

• Rotation speed monitoring and keyphase signal provision for steam turbines, gas turbines and centrifugal compressors in power and petrochemical industries
• Zero-speed interlock protection during unit shutdown and anti-reverse rotation safety control during startup
• Speed reference configuration for rotating equipment fault diagnosis and spectrum analysis
• Spare replacement and system upgrade for legacy 3500 series TSI monitoring racks