Product Overview
With a full-scale range of 0-4 mils pp and frequency response from 5 Hz to 6000 Hz, the Bently Nevada 990-04-50-03-01 delivers precise vibration monitoring for critical rotating machinery. This 990 Vibration Transmitter accepts one non-contacting 3300 NSv Proximity Probe and extension cable, converting shaft displacement into a 4-20 mA signal for reliable machine protection. Manufactured in the U.S.A., this unit combines accuracy with rugged construction for long-term industrial use.
Technical Specifications
The Bently Nevada 990-04-50-03-01 offers these key parameters:
- Full-scale option: 0-4 mils pp (0-100 μm pp)
- System length: 5.0 metres (16.4 feet)
- Mounting: DIN clips and screws (option 03)
- Agency approval: CSA Division 2 (option 01)
- Input: 1 non-contacting 3300 NSv Proximity Probe and extension cable
- Power: +12 to +35 Vdc at transmitter terminal
- Maximum loop resistance: 1,000 Ω including cable at 35 Vdc
- Current limiting: 23 mA typical
- 4-20 mA loop accuracy: Within ±1.5% over specified full-scale range (additional to Prox Out Incremental Scale Factor)
- Probe gap: 0.5 to 1.75 mm (20 to 55 mils)
- NOT OK/signal defeat: Output goes to less than 3.6 mA within 100 µs, restores in 2-3 seconds
- Frequency response: 5 Hz to 6,000 Hz +0, -3 dB
- Minimum target size: 9.5 mm (0.375 in) diameter
- Leadwire length: Maximum 3 metres (10 feet) for Proximitor Sensor Output (BNC)
- Weight: 0.43 kg (0.9 lbm)
Industry Applications
The Bently Nevada 990-04-50-03-01 excels in monitoring shaft vibration on steam turbines, centrifugal compressors, and large pumps. Its fast NOT OK response protects machinery by shutting down the 4-20 mA loop within microseconds of a fault, reducing potential damage. The 0-4 mils full-scale range suits close-clearance machines where small displacements indicate trouble. For example, in a refinery compressor train, this transmitter provides early warning of bearing wear or imbalance.
Installation & Setup Guidance
When installing the Bently Nevada 990-04-50-03-01, ensure the probe is gapped between 0.5 and 1.75 mm from the target. Use the provided DIN clips and screws for mounting. The system length is fixed at 5.0 metres, so plan cable routing accordingly. Power the transmitter with +12 to +35 Vdc, observing maximum loop resistance of 1,000 Ω. Adjust zero and span using non-interacting external adjustments. For hazardous area locations (CSA Division 2), use a 28 V power supply.
Selection Guide & Purchasing Advice
Before purchasing the Bently Nevada 990-04-50-03-01, confirm your system requires the 0-4 mils full-scale range and 5.0 metre cable. Verify compatibility with existing 3300 NSv probes. PLC Source PRO (available at ubest101) stocks this exact model with the CSA Division 2 approval, ensuring reliable delivery for critical applications. For technical questions, contact our team.