Product Description:

The Bently Nevada 149744 is an integral Internal Termination Console (ITC), specifically designed as a Digital I/O Termination Module within the 3500 Series Machinery Protection System. This component serves as a vital interface between the internal backplane of the 3500 rack and external control systems or emergency shutdown (ESD) circuits. It allows for reliable signal integrity, fulfilling the requirements of the API 670 machinery protection standard.

Unlike standard external termination blocks that are mounted outside the rack, the 149744 is designed for rear installation directly into the 3500 rack. It ensures that relay contacts (Normally Open, Normally Closed, and Common) are easily accessible for field wiring, thus maintaining secure and efficient connections to your machinery monitoring system.

Key Features & Functions:

1. Relay Contact Termination:

The 149744 provides flexible relay contact termination for the 3500/32M (4-Channel Relay Module) and 3500/33 (16-Channel Relay Module). The relay contacts are designed to support a variety of configurations, allowing independent relay circuits to be easily connected to the system.

• Contact Ratings: Typically 5A @ 24 Vdc / 5A @ 240 Vac (Resistive)

• Wiring Connections: Euro-style removable terminal blocks

• Wire Gauge Support: 12 AWG (2.0 mm²) to 22 AWG (0.5 mm²)

2. Redundancy Support (TMR Version):

The 149744-02 model is specifically designed for Triple Modular Redundant (TMR) applications. It features specialized voting logic hardware that ensures no single relay failure will cause a false trip or prevent a genuine machine fault from triggering a trip action. This ensures the highest reliability and safety in critical applications.

3. Flexible Relay Logic:

The 149744 offers programmable relays, allowing you to set up various relay logic based on the system’s configuration. The available relay types include:

• OK Relay: Indicates the health status of the 3500 rack and its transducers.

• Alert/Danger Relays: Triggered by vibration or position setpoints.

• Not-OK/Bypass: Indicates when a channel is bypassed for maintenance, ensuring no false alerts are generated during routine servicing.

4. Maintenance-Friendly Design:

The 149744 simplifies maintenance by enabling the replacement of 3500/32M or 3500/33 monitor cards from the front of the rack, without needing to disconnect the field wiring from the rear I/O module. This feature reduces downtime and enhances system reliability.

Installation & Wiring:

The 149744 is mounted in the rear of the 3500 rack behind the relay monitor. Proper installation involves:

• Grounding: Shielded wiring should be terminated at the designated "Shield" or "Ground" pins on the 149744 module to minimize electromagnetic interference (EMI) and ensure reliable performance.

• Arc Suppression: When handling inductive loads, such as large solenoid valves, external arc suppression is recommended to protect the physical contacts of the 149744 from damage caused by arcing.

Technical Specifications:

Application Scenarios:

The Bently Nevada 149744 is essential for high-performance machinery protection in systems where fault monitoring and emergency shutdown (ESD) circuits are integral. It is designed for use in:

• Industrial Machinery: Protecting critical components in turbines, compressors, and pumps.

• Power Generation: Ensuring the safe operation of transformers and generators in power plants.

• Heavy Machinery Monitoring: Used in environments requiring robust, real-time protection for equipment operating under high mechanical stresses.