Bently Nevada 990-04-50-02-00 990 Vibration Transmitter

Overview

The Bently Nevada 990-04-50-02-00 990 Vibration Transmitter is designed for OEMs working with centrifugal air compressors, small pumps, motors, or fans. This two-wire, loop-powered transmitter provides a 4 to 20 mA proportional vibration signal, simplifying the integration of vibration monitoring into control systems. It works with the 3300 NSv Proximity Probe and its matching extension cables, offering a solution for machinery protection and alarming in industrial applications.

Technical Specifications

Electrical Specifications

• Input:

  • Accepts 1 non-contacting 3300 NSv Proximity Probe and extension cable.

• Power Requirements:

  • Requires +12 to +35 Vdc input at the transmitter terminal.

• Signal Output:

  • 4 to 20 mA over full-scale range in 2-wire configuration.

• Loop Accuracy:

  • ±1.5% over specified full-scale range, measured across a 250 Ω loop resistance.

• Probe Gap:

  • Must be between 0.5 and 1.75 mm (20 to 55 mils) from the target.

• Maximum Loop Resistance:

  • 1,000 Ω, including the cable at 35 Vdc.

• Current Limiting:

  • 23 mA typical.

• Zero and Span Adjustments:

  • Non-interacting external adjustments for calibration.

• Not OK/Signal Defeat:

  • Signal output drops below 3.6 mA within 100 µs during a Not OK condition. Restores within 2-3 seconds after removal of fault.

• Power-up Inhibit:

  • Signal stays below 3.6 mA (Not OK) for 2-3 seconds after power is applied.

Proximitor Sensor Output

• Compatibility:

  • Works with ungrounded, portable test equipment. Use 122115-01 Test Adapter for grounded, AC-powered test equipment for isolation.

• Prox Out Linear Range:

  • 0.25 mm (10 mils) to 1.4 mm (55 mils).

• Incremental Scale Factor:

  • 7.87 mV/µm (200 mV/mil), ±6.5% typical.

• Temperature Stability:

  • Scale factor remains within ±10% from 0°C to +70°C (+32°F to +158°F).

• 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 meters (10 feet) for Proximitor Sensor Output (BNC connector).

Environmental Specifications

• Transmitter Operating Temperature:

  • -35°C to +85°C (-31°F to +185°F).

• Transmitter Storage Temperature:

  • -52°C to +100°C (-62°F to +212°F).

• Probe Operating Temperature:

  • -52°C to +177°C (-62°F to +351°F).

• Probe Storage Temperature:

  • -52°C to +177°C (-62°F to +351°F).

• Relative Humidity:

  • 100% condensing (non-submerged), with coaxial connectors protected.

Mechanical Specifications

• Transducer Tip Material:

  • Polyphenylene sulfide (PPS).

• Transducer Case Material:

  • AISI 303 or 304 Stainless Steel (SST).

• Probe Cable:

  • 75Ω coaxial, FEP-insulated.

• Cable Armor:

  • Optional flexible AISI 302 SST with FEP outer jacket.

• Tensile Strength:

  • 222 N (50 lbf) maximum between the probe case and probe lead.

• Transmitter Weight:

  • 0.43 kg (0.9 lb).

• Total System Weight:

  • 0.82 kg (1.8 lb).