Bently Nevada 3500/70 125720-01 Speed / Keyphasor Module

Bently Nevada 3500/70 125720-01 is a speed and keyphasor monitoring module for the 3500 machinery protection system. It receives pulse signals from keyphasor probes to measure shaft rotational speed, rotor phase angle and provide once-per-revolution reference signal for vibration spectrum and orbit analysis.

This module supports overspeed alarm and trip protection, with built-in sensor fault diagnosis. It adopts hot-swap design, and delivers keyphasor reference signal to other monitor modules inside the rack, widely used for turbine monitoring cabinet maintenance, spare parts replacement and rotating machinery protection system retrofit projects.

Data Parameters

• 1. Brand: Bently Nevada (Baker Hughes).

• 2. Model: 3500/70, Part Number:125720-01.

• 3. Product Type: Speed & Keyphasor Monitor Module.

• 4. Product Series: 3500 Machinery Protection System.

• 5. Input: Keyphasor probe pulse signal input.

• 6. Measurement: Rotational speed, shaft phase reference.

• 7. Protection: Configurable overspeed alarm and trip thresholds.

• 8. Feature: Hot swappable without system shutdown.

• 9. Diagnosis: Probe open circuit, short circuit and signal fault detection.

• 10. Operating Temperature: 0℃ ~ +60℃.

Core Functions

• 1. Capture pulse signals from keyphasor transducer to calculate real-time rotating speed of shafts.

• 2. Generate once-per-revolution keyphasor reference signal for vibration waveform and orbit analysis.

• 3. Implement overspeed protection logic, trigger alarm or trip when rotational speed exceeds preset limit.

• 4. Continuously detect probe and wiring faults, and send fault alerts to the rack diagnostic system.

• 5. Distribute phase reference signal to other monitoring modules inside the 3500 rack for synchronized data acquisition.

Application Scenarios

• 1. Thermal power plant steam turbine overspeed and keyphasor monitoring cabinet spare parts replacement.

• 2. Oil & gas large centrifugal compressor rotating speed protection system upgrade project.

• 3. Petrochemical plant critical rotating equipment phase reference and overspeed monitoring spare renewal.

• 4. Steel, paper and mining factories high-speed rotating machinery safety protection backup inventory.

• 5. Legacy Bently Nevada 3500 machinery monitoring system aging speed module replacement project.

FAQ

• 1. Q: What is Bently Nevada 3500/70 125720-01?
      A: It is speed and keyphasor monitor module for Bently Nevada 3500 machinery protection system, used for shaft speed measurement and phase reference.

• 2. Q: What is the Keyphasor function for?
      A: It provides one pulse per shaft revolution, used as phase reference for vibration spectrum and orbit plot analysis.

• 3. Q: Can 3500/70 be hot swapped?
      A: Yes, it supports hot swap, module replacement will not shut down the whole machinery monitoring rack.