Bently Nevada 3500/25 125800-02 Keyphasor Input Card

Product Overview

The Bently Nevada 125800-02 functions as the high-integrity isolated I/O interface for the 3500/25 Keyphasor® module. This card processes once-per-turn pulses from proximity probes or magnetic pickups, providing the essential timing and phase reference data required for vibration analysis. We supply this module as 100% Brand New and Original, featuring advanced galvanic isolation to ensure signal purity in complex industrial grounding environments.

Technical Specifications

Engineering Advantages

• Galvanic Ground Loop Isolation: The 125800-02 physically separates field transducer signals from the 3500 rack's internal electronics. This isolation suppresses common-mode noise and prevents electrical interference caused by potential differences between field sensors and the central control room.

• Stable Phase Reference Timing: By providing a clean, isolated pulse to the 3500/25 main module, this I/O card ensures accurate phase angle measurements. Precise timing is vital for balancing rotors and identifying machine malfunctions like misalignment or shaft cracks.

• Versatile Transducer Interface: The module accepts signals from both passive magnetic pickups and active proximity probes. Engineers can configure the input threshold and hysteresis settings within the 3500 software to match the specific voltage output of the field-mounted sensor.

• Ruggedized Internal Termination: The rear-mount screw terminals provide a secure, vibration-resistant connection point for field wiring. This "Internal Termination" design simplifies cabinet layout by eliminating the need for additional external termination blocks (ETBs) and interconnect cables.

FAQs

1. What is the main difference between 125800-01 and 125800-02?

The 125800-02 features full signal isolation. We recommend the isolated -02 version for all installations where the proximity probe and the 3500 rack do not share an identical ground potential, as it prevents signal corruption and false trips.

2. Can I use the 125800-02 with a 3500/50 Tachometer module?

No. The 125800-02 is designed exclusively for the 3500/25 Keyphasor® module. While both handle speed signals, the Tachometer module requires a different I/O interface to manage the high-frequency pulse trains used for continuous speed control.

3. Does this module support hot-swapping?

Yes, you can install or remove the I/O module while the 3500 rack is powered, provided you follow proper safety procedures. However, removing the Keyphasor I/O will cause any vibration monitors relying on that phase reference to go into a "Not OK" status or lose phase data.

4. How do I verify the isolation integrity of the 125800-02?

During commissioning, use a digital multimeter to confirm that there is no electrical continuity between the field wiring shields and the 3500 rack chassis. The isolated circuitry within the 125800-02 maintains this separation automatically to protect signal fidelity.