Configured for continuous acceleration monitoring in machinery protection systems, the Bently Nevada 3300/26-XX-XX-XX-00-00-01-00 (3300/26 RMS Monitor) provides direct physical/electrical execution. This dual-channel module interfaces with seismic accelerometers to process vibration signals, providing conditioned 4-20 mA outputs proportional to the Root Mean Square (RMS) acceleration. The monitor performs signal integration and filtering to facilitate standardized interface with site-level DCS or PLC data acquisition systems.

Model Matrix & Suffix Breakdown

• 3300/26: Dual Accelerometer RMS Monitor.

• XX: Input/Output configurations (as per catalog ordering codes).

• 00-00-01-00: Standard factory base configuration for agency and interface options.

Hardware Specifications

Mechanical Monitoring and Signal Conditioning

Effective rotor dynamics analysis requires precise signal conditioning for seismic vibration sensors. The 3300/26 module provides high-fidelity processing of accelerometer inputs, ensuring that signal attenuation and phase shifts remain within defined tolerances. Operators must perform regular gap voltage or bias current validation to confirm sensor health. Cross-talk suppression is achieved through rigorous shielding and grounding protocols at the module backplane, ensuring that individual acceleration channels remain isolated from electromagnetic interference present in high-density rack environments.

Ordering info

• 1 3300/26-XX-XX-XX-00-00-01-00 Dual Accelerometer RMS Monitor Module

• 1 Front-panel configuration/calibration key

• 1 Installation and maintenance reference manual

Field Installation Guidelines

• Rack Mounting

• Slide the module into the designated slot of the 3300 Series rack, ensuring proper alignment with the backplane connectors.

• Secure the front-panel captive screws to maintain grounding and physical retention of the module.

• Signal Wiring

• Route accelerometer cables through dedicated conduits, keeping them separate from high-voltage AC lines.

• Connect signal shields to the designated common ground terminals on the rear I/O card to prevent ground loop-induced measurement errors.

Frequently Asked Questions

• Does the 3300/26 support hot-swapping?

  The module can be removed from the rack while powered, but it is recommended to disable associated alarm logic to prevent spurious trips during removal.

• Can the module be configured for non-RMS outputs?

  The 3300/26 is specifically designed for RMS acceleration output; peak detection or other processing methods are handled by different monitor modules.

• What is the impact of relative humidity?

  The unit is rated for up to 95% non-condensing humidity. Condensation within the rack must be avoided to prevent signal leakage or electrical shorts on the backplane.

• How is the 4-20 mA output calibrated?

  Calibration is managed through front-panel interface points using a signal generator to inject reference acceleration signals and adjusting the internal gains.

• Is the frequency response adjustable?

  The internal filters are factory-set. The raw bandwidth is 2.7 Hz to 90 kHz, while integrated signals are limited to 10 Hz to 90 kHz.

• What impedance does the monitor present to the accelerometer?

  The input circuitry is designed to match standard industrial accelerometers, with an output impedance of 100 ohm for the signal conditioning loop.

• Does this module require a separate power supply?

  The module receives power from the 3300 series rack backplane; ensure the rack power supply is sized to handle the cumulative load of all modules.

• What does a "Not OK" indicator signify?

  A "Not OK" status indicates a loss of bias voltage from the accelerometer or an internal monitor failure, signaling that the current measurement is invalid.