Product Description

Overview

The Bently Nevada 133442-01 is a Tachometer Input/Output (I/O) Module with internal terminations, designed for the 3500/50M Tachometer Module in the 3500 Series Machinery Protection System. This rear-mounted module provides a direct interface for speed sensors, including Proximitor® transducers and passive magnetic pickups, delivering precise rotational speed, acceleration, and direction signals to the monitoring system.

The integrated screw terminals allow direct field wiring to the module without the need for additional terminal blocks or wiring harnesses, simplifying installation and reducing cabinet complexity.

Key Features

High-Frequency Signal Processing

• Input frequency handling up to 20 kHz, supporting high-speed turbines and motors

• Measures speeds from 1 rpm up to 99,999 rpm

• Processes rotor acceleration for rapid over-speed or zero-speed detection

Signal Conditioning & Threshold Control

• Auto-threshold: Adjusts automatically for input above 1 rpm (0.0167 Hz)

• Manual threshold: Configurable from +9.5 Vdc to -23.5 Vdc

• Hysteresis: Programmable from 0.2 V to 2.5 V to prevent false triggers from noisy signals

Precision & Reliability

• Speed accuracy:

• <100 rpm: ±0.1 rpm

• 100–10,000 rpm: ±1 rpm

• 10,000 rpm: ±0.01% of actual shaft speed

• Update rate: ~100 ms for rapid data refresh

• Robust recorder outputs: Isolated +4 to +20 mA proportional to full-scale speed

• Short-circuit protection on output channels ensures continuous monitoring

Operational Advantages

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

• Built-in -24 Vdc transducer power supply (up to 40 mA per channel)

• Ideal for simplex configurations requiring compact wiring solutions

• Compatible with dual-channel 3500/50M modules for enhanced monitoring

Technical Specifications

Applications

The 133442-01 is used in industrial machinery monitoring where precise speed measurements are critical:

• Turbine and motor rotational speed monitoring

• Rotor acceleration and deceleration detection

• Keyphasor® signal generation for vibration and phase analysis

• Systems where simplified cabinet wiring is a priority

FAQ

Q: What is the primary function of the 133442-01 module?
A: It collects speed and acceleration signals from proximity probes or magnetic pickups and provides conditioned inputs to the 3500/50M tachometer monitor.

Q: Can this module be used in TMR (Triple Modular Redundant) systems?
A: For TMR configurations, the 133450-01 external termination module is recommended; the 133442-01 is best for simplex or non-redundant setups.

Q: How does the module handle noisy input signals?
A: Hysteresis and auto/manual thresholding prevent false triggers, ensuring accurate speed and acceleration measurements even in electrically noisy environments.

Q: Are the outputs protected against faults?
A: Yes, short-circuit protection is built into the recorder outputs, maintaining monitoring reliability.