Product Introduction
When unexpected machine vibration leads to costly downtime, the Bently Nevada 990-05-70-03-CN provides precise, real‑time monitoring. This 990 Vibration Transmitter accepts one non‑contacting 3300 NSv Proximity Probe and extension cable, converting shaft displacement into a standard 4‑20 mA signal. Designed for continuous operation in demanding industrial environments, the 990-05-70-03-CN helps extend equipment life and reduce unplanned maintenance expenses.
Technical Specifications
Key performance parameters of the Bently Nevada 990-05-70-03-CN include:
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Full‑scale Range: 0–5 mils pp (0–125 µm pp) – Option 05
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System Length: 7.0 meters (23.0 feet) – Option 70
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Mounting: DIN clips and screws – Option 03
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Power Input: +12 to +35 Vdc at transmitter terminal
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Output: 4‑20 mAdc over full scale, 2‑wire configuration
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Loop Accuracy: ±1.5% over full scale (measured across 250 Ω, in addition to Prox Out Incremental Scale Factor)
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Maximum Loop Resistance: 1,000 Ω including cable 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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Transmitter Weight: 0.43 kg (0.9 lbm)
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Minimum Target Size: 9.5 mm (0.375 in) diameter
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Probe Gap: 0.5–1.75 mm (20–55 mils) from target for full range
Real‑World Applications
The Bently Nevada 990-05-70-03-CN excels in critical rotating machinery monitoring. In a steam turbine installation, its 5 Hz to 6,000 Hz frequency response captures both low‑speed shaft bow and high‑speed blade‑pass vibrations. For a large centrifugal compressor, the 4‑20 mA loop output feeds directly into a DCS or PLC, enabling trending and alarm management. The 990-05-70-03-CN also supports predictive maintenance programs in paper mills, refineries, and power plants, where early detection of bearing wear or imbalance can save thousands in repair costs.
Installation & Setup Guidance
Mount the Bently Nevada 990-05-70-03-CN using DIN clips and screws (option 03) on a standard DIN rail within a suitable enclosure. Connect a 3300 NSv Proximity Probe and extension cable to the input; the system length option 70 provides a 7.0‑meter cable. Wire the power supply (+12 to +35 Vdc) and the 4‑20 mA loop in a 2‑wire configuration. Adjust zero and span using the non‑interacting external adjustments. Ensure the probe gap is between 0.5 and 1.75 mm (20–55 mils) from the target to guarantee full‑scale output. For non‑hazardous, Zone 2 or Div 2 certified locations, power with a 28 V supply.
Maintenance & Reliability
Routine checks of the Bently Nevada 990-05-70-03-CN focus on verifying the loop power supply remains within +12 to +35 Vdc and that the probe gap stays within specification. Inspect cable connections for corrosion or damage; the maximum leadwire length for the Proximitor Sensor Output (BNC connector) is 3 meters (10 feet). The transmitter’s signal defeat feature automatically drives the output below 3.6 mA within 100 µs of a Not OK condition, and restores it within 2–3 seconds after the fault clears. This self‑diagnostic capability minimizes false trips and enhances overall system reliability, directly supporting a positive ROI by reducing unplanned downtime.
Selection Guide & Purchasing Advice
When ordering the Bently Nevada 990-05-70-03-CN, verify the full‑scale option (05: 0–5 mils pp), system length (70: 7.0 m), and mounting (03: DIN clips and screws). Confirm the agency approval option (CN) meets your regional requirements. The transmitter is made in the U.S.A. For a reliable supply of genuine Bently Nevada parts, including the 990-05-70-03-CN, choose PLC Source PRO. Visit ubest101.myshopify.com for additional automation spares and technical support.