Product Overview: Bently Nevada 990-04-50-02-05 990 Vibration Transmitter
When vibration monitoring is critical for machine protection, the Bently Nevada 990-04-50-02-05 delivers reliable 4-20 mA output with fast signal defeat on faults. This 990 Vibration Transmitter accepts one non-contacting 3300 NSv Proximity Probe and extension cable, converting vibration measurements into a proportional 4-20 mA signal. It is designed for hazardous and non-hazardous environments, with agency approvals including CSA Division 2, ATEX Zone 0, ATEX Zone 2, and ABS maritime approval.
Technical Specifications Breakdown
| Parameter |
Value |
| Full-scale Option |
0-4 mils pp (0-100 μm pp) |
| System Length Option |
5.0 metres (16.4 feet) |
| Mounting Option |
02 Bulkhead screws |
| Agency Approvals |
CSA Division 2, ATEX Zone 0, ATEX Zone 2, ABS maritime |
| Input |
1 non-contacting 3300 NSv Proximity Probe and extension cable |
| Power Requirement |
+12 to +35 Vdc at transmitter terminal |
| Maximum Loop Resistance |
1,000 Ω including cable at 35 Vdc |
| Current Limiting |
23 mA typical |
| 4 to 20 mA Signal Output |
4 to 20 mAdc over full-scale range in 2-wire configuration |
| 4 to 20 mA Loop Accuracy |
Within ±1.5% over full-scale range (across 250 Ω load, excluding Prox Out Incremental Scale Factor) |
| Probe Gap |
0.5 to 1.75 mm (20 to 55 mils) from target |
| Frequency Response |
5 Hz to 6,000 Hz +0, -3 dB |
| Minimum Target Size |
9.5 mm (0.375 in) diameter |
| Leadwire Length (BNC) |
Maximum 3 meters (10 feet) |
| Transmitter Weight |
0.43 kg (0.9 lbm) |
Industry Applications: Real-World Use Cases
The Bently Nevada 990-04-50-02-05 is ideal for monitoring rotating machinery such as turbines, pumps, and compressors. In environments prone to sensor failure, its NOT OK signal defeat feature forces the output below 3.6 mA within 100 µs of a fault, alerting control systems to take immediate action. This capability is critical in petrochemical plants, power generation, and marine applications where unplanned downtime can be costly. The transmitter's ±1.5% loop accuracy ensures precise vibration data, enabling predictive maintenance schedules.
Installation & Setup Guidance
Mount the Bently Nevada 990-04-50-02-05 using the bulkhead screw option. Ensure the probe gap is set between 0.5 and 1.75 mm to achieve full-scale range. The BNC leadwire from the Proximitor Sensor output must not exceed 3 meters to maintain signal integrity. Power the transmitter with +12 to +35 Vdc at the terminal, observing the maximum loop resistance of 1,000 Ω at 35 Vdc. Use non-interacting external adjustments for zero and span calibration.
Maintenance & Reliability
The Bently Nevada 990-04-50-02-05 requires minimal maintenance due to its robust design. The non-interacting zero and span adjustments simplify calibration, reducing labor costs. The NOT OK/signal defeat feature automatically detects probe or cable faults, protecting downstream equipment. For long-term reliability, verify the probe gap and cable connections during routine inspections. This transmitter withstands harsh conditions thanks to its ATEX and CSA approvals.
Selection Guide & Purchasing Advice
When selecting the Bently Nevada 990-04-50-02-05, verify the full-scale option (0-4 mils pp) and system length (5.0 metres) match your application requirements. Confirm the mounting option (bulkhead screws) and agency approval (Option 05) are suitable for your hazardous area classification. For genuine spares and fast delivery, trust PLC Source PRO (formerly ubest101). We stock this exact model and support industrial automation needs worldwide.