Bently Nevada 139554-01 3500/45 AC LVDT Position I/O Module

Description

The Bently Nevada 139554-01 is an AC LVDT position I/O module with internal terminations designed for machinery position monitoring and protection applications. Installed in a full-height rear slot of a Bently Nevada 3500 system rack, the module routes input signals from AC Linear Variable Differential Transformers (AC LVDTs) directly to the 3500/45 Position Monitor main board. It provides continuous transducer excitation using a 2.3 Vrms, 3400 Hz sine wave signal and supports key parameters including Case Expansion and Valve Position measurements. Process interfaces feature +4 to +20 mA recorder current outputs for local control integration and dedicated inhibit control inputs.

Features

• Accepts up to 4 AC LVDT transducer signal inputs via internal terminal connections.
• Provides a dedicated 2.3 Vrms, 3400 Hz sine wave transducer excitation power supply.
• Features +4 to +20 mA proportional current outputs for recorder data transmission.
• Includes hardware inhibit (INHB) and return terminal pins for remote function control.
• Integrates internal screw-terminal headers directly on the rear module interface.

Applications

• Case expansion monitoring on steam turbine casings.
• Valve position monitoring for process inlet valve stems and governor control valves.
• Continuous position tracking in rotating machinery protection systems.

Ordering Information

Technical Specifications

Connections/Interfaces

Installation Guidelines

• Install the module into the full-height rear slot directly behind the 3500/45 Position Monitor main board.
• Secure the top and bottom captive screws to maintain proper chassis ground and mechanical integrity.
• Route transducer signal cables through internal terminal blocks with appropriate strain relief.
• Connect shield wires directly to designated SHLD terminal points to minimize electromagnetic noise interference.

Compliance and Certifications

• EMC Directives: European Community Directive 2014/30/EU; EN 61000-6-2, EN 61000-6-4
• Electrical Safety: European Community Directive 2014/35/EU; EN 61010-1
• RoHS Directives: European Community ROHS Directive 2011/65/EU; China RoHS SJ/T 11364-2024 (EFUP 15 years)
• Maritime Approvals: DNV GL rules for classification; ABS Rules for Condition of Classification
• Hazardous Area Approvals: cNRTLus Class I, Zone 2 / Class I, Division 2, Groups A, B, C, D (T4 @ Ta = -20 degC to +65 degC); ATEX/IECEx Ex nA nC ic IIC T4 Gc / Ex ec nC ic IIC T4 Gc