Product Overview
When unexpected machinery vibration threatens uptime, the Bently Nevada 990-10-70-02-01 vibration transmitter delivers precise, real-time monitoring. This 990 Vibration Transmitter accepts one non-contacting 3300 NSv proximity probe and extension cable, converting dynamic shaft displacement into a standard 4-20 mA loop signal. With a full-scale range of 0–10 mils pp (0–250 μm pp) and a system length of 7.0 meters, the 990-10-70-02-01 is engineered for continuous operation in demanding industrial environments.
Technical Specifications Breakdown
The 990-10-70-02-01 offers key parameters that ensure accurate vibration measurement and robust performance.
| Parameter |
Value |
| Input |
Accepts 1 non-contacting 3300 NSv Proximity Probe and extension cable |
| Power Requirement |
+12 to +35 Vdc at transmitter terminal |
| 4-20 mA Output |
4-20 mAdc over full-scale range, 2-wire configuration |
| Loop Accuracy |
Within ±1.5% over full-scale range (excluding Prox Out Incremental Scale Factor) |
| Probe Gap Range |
0.5 to 1.75 mm (20 to 55 mils) |
| Maximum Loop Resistance |
1,000 Ω including cable at 35 Vdc |
| Current Limiting |
23 mA typical |
| Frequency Response |
5 Hz to 6,000 Hz +0, -3 dB |
| Not OK/Signal Defeat |
Output <3.6 mA within 100 µs; restores within 2-3 seconds after condition cleared |
| Weight |
0.43 kg (0.9 lbm) |
Each spec is critical: the non‑interacting zero and span adjustments simplify calibration, while the Not OK/signal defeat ensures immediate indication of probe or electronics failure. The unit is approved for CSA Division 2 hazardous locations, requiring 28 Vdc power supply.
Industry Applications
This vibration transmitter excels in rotating machinery protection—compressors, pumps, turbines, and fans. In a refinery, the 990-10-70-02-01 continuously monitors shaft vibration, alerting operators to imbalance or bearing wear before catastrophic failure. Its fast Not OK response (under 3.6 mA within 100 µs) provides early fault detection, reducing unplanned downtime. For high-speed spindles in manufacturing, the 5 Hz to 6 kHz bandwidth captures both low-frequency eccentricity and high-frequency gear mesh vibrations.
Installation & Setup Guidance
Mount the 990-10-70-02-01 using bulkhead screws (Mounting Option 02). Ensure the System Length Option 70 (7.0 meters) provides adequate cable reach from probe to transmitter. Critical: gap the 3300 NSv probe between 0.5 and 1.75 mm from the target. A gap outside this range can prevent the transmitter from achieving full-scale output. Leadwire maximum for Proximitor Sensor Output (BNC connector) is 3 meters (10 feet). Use a twisted shielded pair for the 4-20 mA loop to minimize noise.
Troubleshooting & Common Issues
If the output reads below 3.6 mA, check for a Not OK condition—caused by probe gap loss, cable faults, or internal electronics issues. The unit tests itself: when fault clears, output restores within 2-3 seconds. Verify loop resistance does not exceed 1,000 Ω at 35 Vdc to avoid saturation. If accuracy drifts, recalibrate zero and span using the non‑interacting external adjustments. The current limiting (23 mA typical) protects downstream devices; a loop current exceeding 23 mA often indicates a wiring short.
Selection Guide & Purchasing Advice
Before ordering, confirm your probe type (3300 NSv series) and required full‑scale range. The 990-10-70-02-01 comes with Full-scale Option 10 (0–10 mils pp); verify that matches your vibration magnitude. For applications needing longer cable runs, consider the 7.0 meter System Length Option 70 is already included—other lengths may require different part numbers. As a trusted supplier of industrial automation parts, ubest101 offers this Bently Nevada 990-10-70-02-01 module with CSA Division 2 approval. Ensure your loop power supply delivers at least +12 Vdc (up to +35 Vdc) at the transmitter terminal.