Bently Nevada 77581-02 Digital Vector Filter 3

Quick Overview

The Bently Nevada 77581-02, also known as the Digital Vector Filter 3 (DVF 3), is a specialized diagnostic instrument for advanced machinery vibration analysis. It is specifically engineered to filter complex vibration signals to extract the $1X$ (synchronous) and $2X$ amplitude and phase information relative to a Keyphasor® pulse. 

Technical Data

• Model: 77581-02

• Series: Digital Vector Filter 3 (DVF 3)

• Input Ports: 3 × BNC (Channel A, Channel B, and Keyphasor)

• Output Ports: 3 × BNC (Buffered outputs)

• Communication: Rear Optical Interface

• Tracking Filter: Adjustable Bandwidth ($12$ to $120$ cpm)

• Interface: 2-Channel LCD display with RPM adjustment knob

• Weight: Approx. 300 g (Module only)

• Origin: Made in USA

Key Features

• Dual-Channel Simultaneous Monitoring: Allows for the concurrent analysis of two vibration sensors (such as X-Y proximity probes) to visualize orbital motion and shaft centerline position.

• Precision Filtering: The tracking filter automatically locks onto the fundamental rotational frequency, isolating machine-specific vibration data from background noise and non-synchronous interference.

• Transient & Steady-State Modes: Optimized for capturing critical data during machine speed changes, ensuring peak amplitudes and phase shifts at critical speeds (resonances) are accurately recorded.

• Tactile User Controls: Equipped with a dedicated RPM adjustment knob and directional keypad for rapid on-site configuration and menu navigation.

• Integrated Keyphasor Support: Utilizes a Keyphasor input to provide the phase reference essential for diagnosing shaft orientation and timing-related faults.

• Portable & Versatile Design: Though lightweight at 300g, its robust build supports both temporary bench-top troubleshooting and permanent rack-mounted installation in test cells.