Introduction
When unplanned machinery downtime disrupts operations, the Bently Nevada 990-04-50-01-05 990 Vibration Transmitter provides critical early warning. Designed to accept a single non-contacting 3300 NSv Proximity Probe, this transmitter delivers accurate, real-time vibration data to prevent catastrophic failures. The 990-04-50-01-05 is part of Bently Nevada's trusted 990 series, engineered for demanding industrial environments.
Technical Specifications
The Bently Nevada 990-04-50-01-05 operates with a full-scale range of 0-4 mils pp (0-100 μm pp) and a system length of 5.0 meters (16.4 feet). It mounts via 35 mm DIN rail clips and carries approvals: CSA Division 2, ATEX Zone 0, ATEX Zone 2, and ABS maritime approval. Key parameters include:
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Power: +12 to +35 Vdc
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Output: 4-20 mA over full-scale range
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Accuracy: ±1.5% over specified full-scale range
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Maximum loop resistance: 1,000 Ω at 35 Vdc
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Current limiting: 23 mA typical
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Frequency response: 5 Hz to 6,000 Hz +0, -3 dB
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Weight: 0.43 kg (0.9 lbm)
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Probe gap: 0.5 to 1.75 mm (20 to 55 mils)
Industry Applications
The industry applications for the Bently Nevada 990-04-50-01-05 include monitoring rotating machinery such as pumps, compressors, turbines, and fans. In a typical setup, the transmitter connects to a 3300 NSv probe and outputs a 4-20 mA signal proportional to vibration amplitude. The NOT OK/signal defeat feature forces output below 3.6 mA within 100 μs upon fault detection, safeguarding downstream logic.
Installation Guide
Mount the 990-04-50-01-05 using the included 35 mm DIN rail clips. Ensure the proximity probe is gapped between 0.5 and 1.75 mm from the target surface. Power the transmitter with +12 to +35 Vdc at the terminal block. Connect the 3300 NSv probe and extension cable; the maximum leadwire length for the Proximitor Sensor Output (BNC) is 3 meters (10 feet). For hazardous area installations, verify the power supply voltage meets zone requirements (28 V for Div 2/Zone 2).
Maintenance & Reliability
The Bently Nevada 990-04-50-01-05 is designed for long-term reliability with no routine calibration needed. However, periodic inspection of probe gap and cable integrity can prevent drift. The transmitter's current limiting (23 mA typical) protects against loop faults. The non-interacting zero and span adjustments allow field re-ranging without affecting calibration. In severe vibration environments, the robust 35 mm DIN rail mounting ensures stable operation.
Selection Guide
When selecting the Bently Nevada 990-04-50-01-05, confirm the full-scale range (0-4 mils in this variant) and system length (5.0 m) match your installation. The 35 mm DIN rail mounting option simplifies integration. Ensure your power supply provides +12 to +35 Vdc and the loop resistance does not exceed 1,000 Ω. For assistance, contact PLC Source PRO (available at ubest101.myshopify.com) for compatible probes and accessories.