3500/44M 176449-03 enhanced keyphasor module

The BENTLY 3500/25-01-01-00 is an enhanced keyphasor module under Bently Nevada’s 3500 Series Rotating Machinery Protection & Monitoring System. As a dedicated keyphasor signal provider for monitor modules in the 3500 rack, it converts input signals from eddy current or electromagnetic sensors into digital keyphasor signals, which are critical for synchronizing rotational parameter measurements (e.g., vibration, speed) of rotating shafts. Below is its comprehensive detailed information:

1. Basic Function

It is a half-height, 2-channel module primarily designed to supply keyphasor signals to monitor modules within the 3500 frame. It can receive input signals from eddy current sensors or electromagnetic sensors, then convert these signals into digital keyphasor signals. These signals indicate the exact moment when the keyphasor mark on the rotating shaft passes the keyphasor probe—laying the foundation for precise phase-aligned measurements of shaft vibration, eccentricity, and other rotational parameters.

2. Input Characteristics

Signal Range: Each keyphasor module can accept 2 input signals (from eddy current sensors or electromagnetic sensors):
- For non-isolated I/O modules: Input signal range is -0.8V to -21.0V.
- For isolated I/O modules: Input signal range is +5V to -11V.Signals exceeding these ranges are clamped within the module to prevent damage.
Speed Requirement: Passive electromagnetic sensors require a shaft speed of >200 rpm (3.3 Hz) to ensure valid signal acquisition.