990-04-50-02-00 | Bently Nevada 990 Series Vibration Transmitter

Product Overview

The Bently Nevada 990-04-50-02-00 functions as a high-precision, two-wire vibration transmitter designed for continuous machinery protection. It accepts signals from a proximity probe and extension cable, converting the complex eddy current data into a linear 4-20 mA DC output proportional to peak-to-peak vibration. This "rackless" solution enables critical monitoring of centrifugal compressors, pumps, and fans without the cost or footprint of a dedicated monitoring rack. We guarantee this unit is 100% brand new and original equipment.

Part Number Breakdown

The 990-04-50-02-00 configuration utilizes Bently Nevada’s modular logic for 5-meter systems:

Technical Specifications

This transmitter conditions signals with high accuracy for 24VDC loops:

• Output Signal: 4-20 mA DC (Proportional to vibration amplitude).

• Full-Scale Range: 0 to 4 mils peak-to-peak (100 μm).

• System Calibration: Fixed for 5.0-meter probe/cable combinations.

• Input Compatibility: Bently Nevada 3300 or 3300 XL 8mm Proximity Probes.

• Power Requirement: 12 to 35 Vdc (Loop-powered).

• Operating Temperature: -35°C to +85°C (-31°F to +185°F).

• Weight: 0.43 kg (0.9 lb) typical.

Engineering Advantages

• Seamless PLC/DCS Integration: The transmitter converts raw proximity signals into a standard 4-20 mA current loop locally. This allows engineers to connect the device directly to any standard analog input card, eliminating the need for specialized vibration monitors.

• Optimized for Bulkhead Mounting: The "02" mounting option provides a flat-surface, screw-down interface. This is ideal for mounting the transmitter directly onto machine skids or inside custom junction boxes where DIN rails are not available or where high-vibration security is paramount.

• Robust Noise Immunity: By conditioning the signal at the source, the 990-04-50-02-00 protects data integrity from electromagnetic interference (EMI) during long-distance transmission to the control room.

• Diagnostic Buffered Output: The unit includes a separate buffered voltage signal. Maintenance personnel connect portable data collectors directly to the transmitter to analyze vibration waveforms in real-time without interrupting the primary 4-20 mA safety loop.

FAQs

• Can I use a 7-meter extension cable with this transmitter?

  No. The 990-04-50-02-00 is factory-calibrated for a 5.0-meter total system length. Using a 7-meter cable will result in a scale factor error and inaccurate vibration readings.

• Does this unit require a separate Proximitor?

  No. The 990 series integrates the Proximitor driver and transmitter into a single module. It replaces the traditional Proximitor for 4-20 mA applications.

• What happens if the probe gap is set incorrectly?

  The transmitter provides "Prox" and "COM" terminals. You should measure the DC gap voltage with a multimeter during installation to ensure the probe is positioned in the center of its linear range (typically -10V DC).

• Is this a genuine Bently Nevada product?

  Yes. We provide only 100% brand new, original factory stock in original Bently Nevada packaging with full manufacturer traceability and quality assurance.