Product Introduction
When unexpected machine vibration leads to costly downtime, the Bently Nevada 990-08-50-03-CN 990 Vibration Transmitter provides reliable, real-time monitoring to protect your rotating equipment. This industrial automation module accepts one non-contacting 3300 NSv Proximity Probe and extension cable, converting vibration displacement into a 4-20 mA signal. With a full-scale range of 0-8 mils pp (0-200 μm pp) and a system length of 5.0 meters (16.4 feet), it is designed for precision in demanding environments. The 990-08-50-03-CN is built to help you avoid unplanned shutdowns and extend machinery life, delivering a strong return on investment through proactive maintenance.
Technical Specifications
The Bently Nevada 990-08-50-03-CN offers key performance parameters critical for accurate vibration monitoring:
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Power Supply: Requires +12 to +35 Vdc input at the transmitter terminal, ensuring flexibility with various industrial power sources.
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Maximum Loop Resistance: 1,000 Ω including cable at 35 Vdc, allowing long cable runs without signal degradation.
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Current Limiting: 23 mA typical, protecting the loop from overcurrent conditions.
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4-20 mA Loop Accuracy: Within ±1.5% over specified full-scale range, ensuring reliable data for analysis.
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Frequency Response: 5 Hz to 6,000 Hz +0, 3 dB, covering the most common vibration frequencies in rotating machinery.
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NOT OK/Signal Defeat: Signal output drops below 3.6 mA within 100 µs after a Not OK condition, with restoration in 2-3 seconds.
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Weight: 0.43 kg (0.9 lbm), lightweight for easy mounting.
Industry Applications
The Bently Nevada 990-08-50-03-CN is ideal for critical rotating assets such as pumps, compressors, turbines, and fans where early fault detection prevents catastrophic failure. For example, in a centrifugal compressor application, its ±1.5% accuracy and 4-20 mA output enable continuous trend monitoring, allowing maintenance teams to schedule repairs during planned outages rather than emergency shutdowns. This directly reduces lost production time and maintenance costs. Similarly, in large industrial fans, the 5 Hz to 6,000 Hz frequency response captures both imbalance and bearing wear signatures, supporting predictive maintenance programs.
Installation & Setup
Proper installation of the Bently Nevada 990-08-50-03-CN ensures optimal performance. The probe must be gapped between 0.5 and 1.75 mm (20 to 55 mils) from the target to achieve full-scale range. The transmitter mounts using DIN clips and screws (mounting option 03). For the Proximitor Sensor Output (BNC connector), keep cable distance to a maximum of 3 meters (10 feet). The transmitter operates in Non-Hazardous, Zone 2 or Div 2 hazardous area locations with a power supply of 28 V. Ensure zero and span adjustments are made non-interactively externally after installation.
Maintenance & Reliability
To maximize the return on your Bently Nevada 990-08-50-03-CN, schedule periodic inspections of the probe gap and cable connections. The enclosed design resists harsh industrial environments, but verify that the transmitter terminals remain clean and corrosion-free. The current limiting feature (23 mA typical) protects the loop, reducing component stress. Regular calibration checks against the ±1.5% accuracy specification help maintain data integrity, supporting long-term, cost-effective machine protection.
Selection Guide & Purchasing Advice
Before purchasing the Bently Nevada 990-08-50-03-CN, confirm that your application requires the 0-8 mils pp full-scale and 5.0-meter cable length. The CN agency approval indicates suitability for specific country requirements. For reliable sourcing, consider ubest101 as a trusted supplier of industrial automation spares. Ensure your system includes a compatible 3300 NSv Proximity Probe and extension cable, and verify that your power source delivers +12 to +35 Vdc at the transmitter terminal.