Product Overview

The Bently Nevada 133434-01 is a high-performance Tachometer I/O Module designed for the 3500 Machinery Protection System. This module serves as the primary interface for speed sensors, providing the 3500/50 Tachometer Main Module with high-fidelity pulse signals from Keyphasor transducers or other magnetic pickups. By accurately measuring rotational speed and phase, it enables the system to calculate critical parameters such as RPM, rotor acceleration, and zero-speed detection. As a fundamental component of Turbine Supervisory Instrumentation (TSI), the 133434-01 is essential for preventing overspeed conditions and providing the phase reference necessary for vibration vector analysis.

Key Technical Characteristics and Hardware Parameters

The 133434-01 is engineered for extreme precision in signal conditioning, ensuring that speed data remains accurate even in high-interference industrial environments.

• Model Identification 3500/50

• Order Number 133434-01

• Module Type Tachometer I/O with Internal Terminations

• Transducer Compatibility Supports Proximity Probes (Keyphasor), Magnetic Pickups, and Active (non-contact) sensors

• Input Frequency Capable of processing signals from 1 pulse per revolution up to 20,000 pulses per second

• Signal Conditioning On-board threshold and hysteresis adjustments to eliminate false triggering from shaft runout or noise

• Termination Style Integrated compression screw terminals for direct wiring of field sensors

• Operating Temperature -30°C to +65°C (-22°F to +150°F)

• Isolation High-voltage galvanic isolation to protect the rack backplane from field-side electrical surges

• Physical Weight 0.40 kg

• Module Dimensions 2.5 x 11.2 x 24.2 cm

Industrial Applications and Operational Use Cases

The 133434-01 Tachometer I/O is a critical requirement for any rotating machinery that relies on speed-based protection and phase-locked vibration monitoring.

• Overspeed Protection Providing rapid-response speed data to trigger emergency trip relays if a steam or gas turbine exceeds its safe operating RPM.

• Phase Reference (Keyphasor) Delivering the 1-per-turn pulse required for synchronous vibration sampling, allowing for the generation of Bode and Polar plots.

• Zero-Speed Detection Confirming a complete stop of the rotor before turning gear engagement or maintenance activities begin.

• Reverse Rotation Detection Identifying improper shaft rotation in pumps and compressors during startup to prevent internal mechanical damage.

• Acceleration Monitoring Tracking the rate of speed change during turbine startup cycles to ensure compliance with thermal stress limits.

By utilizing the 133434-01 with internal terminations, installation is simplified, and the reliability of the speed signal path is maximized, ensuring the safety of high-value industrial assets across the power generation and oil and gas sectors.