Overview

The Bently Nevada 133396-01 is a dedicated internal termination I/O interface designed for use with the 3500/50M Tachometer monitoring system. Installed at the rear of the rack, it provides direct connectivity between field-mounted speed sensors and the front-end monitoring module.

This module is engineered for continuous rotational speed measurement in critical rotating equipment. It enables accurate acquisition of pulse signals from various transducers and ensures stable signal delivery for real-time analysis within the 3500 protection platform.

Technical Specifications

Core Functional Capabilities

Dual-Channel Speed Signal Interface

The module supports two independent input channels, allowing simultaneous monitoring of separate shafts or redundant measurement of a single rotating asset. This architecture enhances system reliability in safety-critical applications.

Multi-Sensor Compatibility

Designed to work with both powered and self-generating sensors, the module accommodates:

• Eddy current proximity probes requiring external power

• Magnetic pickups producing passive voltage signals

This flexibility simplifies integration across different machinery types.

Accurate Speed and Motion Detection

When paired with the 3500/50M monitor, the module enables:

• Real-time RPM tracking

• Acceleration and deceleration monitoring

• Zero-speed detection for turning gear systems

These measurements are essential for turbine protection, compressor monitoring, and startup/shutdown sequencing.

Integrated Signal Conditioning

Built-in filtering circuitry minimizes electrical noise and signal distortion commonly found in industrial environments. This ensures stable pulse recognition and prevents erroneous overspeed or underspeed alarms.

Mechanical and Installation Features

Internal Termination Design

Field wiring is landed directly onto labeled screw terminals, eliminating the need for external termination panels. This simplifies installation and reduces cabinet space requirements.

Compact Half-Height Form Factor

The half-height design allows two I/O modules to share a single rack slot. This is particularly useful for implementing redundant speed measurement paths without increasing rack footprint.

Seamless Rack Integration

The module interfaces directly with the 3500 backplane, ensuring reliable signal routing to the monitoring module without additional adapters or conversion hardware.

Application Scenarios

• Steam and gas turbine speed monitoring

• Compressor anti-surge and overspeed protection

• Gearbox rotational analysis

• Pump and motor condition monitoring

• Safety-critical redundant speed measurement systems

FAQ

What is the primary function of the 133396-01 module?

It provides the physical interface between speed sensors and the 3500/50M monitor, enabling accurate acquisition of rotational speed signals.

Can it support both active and passive sensors?

Yes, it supports powered Proximitor sensors as well as passive magnetic pickups, making it suitable for a wide range of applications.

Does this module support redundant configurations?

Yes, dual-channel input and half-height mounting allow redundant sensor configurations for high-reliability systems.

Is external termination required?

No, this version uses internal termination, meaning all field wiring connects directly to the module.