Bently Nevada 990-04-50-03-00 Transmitter

Bently Nevada 990-04-50-03-00 Vibration Transmitter

Product Introduction

The Bently Nevada 990-04-50-03-00 offers reliable vibration monitoring for rotating machinery. This 990 Vibration Transmitter converts probe signals into a standard 4-20 mA output. It serves industrial applications where continuous monitoring is critical. Many users prefer this model for its simple design and robust performance.

Technical Specifications

Full-scale Option: The device supports 0-4 mils pp (0-100 μm pp). This range suits common vibration monitoring tasks.

System Length Option: It includes a 5.0 metre (16.4 feet) cable. This length provides flexible installation options.

Mounting Option: The transmitter comes with DIN clips and screws. These parts simplify panel mounting.

Agency Approval Option: Not required for this specific configuration.

Power Requirements: The unit needs +12 to +35 Vdc input at its terminal. This wide range allows different power supplies.

Signal Output: It delivers 4 to 20 mAdc over the full-scale range. The two-wire setup reduces wiring needs.

Loop Accuracy: Accuracy stays within ±1.5% over the specified range. This rating applies from the TEST signal to a 250 Ω load. Note that this error adds to the Prox Out Incremental Scale Factor.

Probe Gap: The probe must sit between 0.5 and 1.75 mm (20 and 55 mils) from the target. This gap ensures correct full-scale operation.

Maximum Loop Resistance: You can use up to 1,000 Ω including cable at 35 Vdc. Higher resistance may cause signal problems.

Current Limiting: The device limits current to 23 mA typically. This feature prevents damage during electrical faults.

Zero and Span: External non-interacting adjustments make calibration easy. You do not need special tools.

NOT OK/Signal Defeat: When a NOT OK condition happens, the output drops below 3.6 mA within 100 µs. After the fault clears, output returns in 2-3 seconds.

Frequency Response: The unit responds from 5 Hz to 6,000 Hz +0, 3 dB. This range covers many machine vibration frequencies.

Minimum Target Size: The target must be at least 9.5 mm (0.375 in) in diameter. Smaller targets can give wrong readings.

Leadwire Length: For the Proximitor Sensor Output (BNC connector), the max cable distance is 3 meters (10 feet).

Mechanical & Environmental Data

Transmitter Weight: The unit weighs 0.43 kg (0.9 lbm). This light weight makes mounting easier.

Hazardous Area Locations: This version works in NonHazardous, Zone 2 or Div 2 areas. A 28 V power supply is recommended for those locations.

Input Type: It accepts one non-contacting 3300 NSv Proximity Probe and an extension cable.

Installation Guide

First, mount the probe between 0.5 and 1.75 mm from the target. Use the included DIN clips and screws to secure the transmitter. Next, connect the 3300 NSv probe and extension cable to the input. Then wire the power terminals to a +12 to +35 Vdc source. The two-wire 4-20 mA loop connects directly to your monitoring system. Additionally, ensure the total loop resistance stays below 1,000 Ω at 35 Vdc. Finally, use the external zero and span adjustments to calibrate the output.

For Proximitor Sensor Output with BNC connector, keep the cable length under 3 metres. The 990 Vibration Transmitter responds within 2-3 seconds after a NOT OK condition clears. Therefore, always verify the probe gap before powering on the system.

Packaging List

• Bently Nevada 990-04-50-03-00 Vibration Transmitter (1 unit)

• DIN clips and screws (mounting kit)

• 5.0 metre system cable (pre-attached)

• Product manual (quick start guide)

Note: The package does not include certificates or warranty documents. These are managed separately by your distributor.

Shipping Information

All orders ship via FedEx, UPS, or DHL. Delivery times depend on your location. Tracking numbers are provided after dispatch.

Frequently Asked Questions (FAQ)

1. What probe works with the Bently Nevada 990-04-50-03-00?
This transmitter only accepts one non-contacting 3300 NSv Proximity Probe. You also need a compatible extension cable.

2. Can I use this device in a hazardous area?
Yes. This specific version (Agency Approval 00) is rated for NonHazardous, Zone 2, or Div 2 locations. Use a 28 V power supply for those areas.

3. How do I know if the probe gap is correct?
The probe must be gapped between 0.5 and 1.75 mm (20 and 55 mils) from the target. If the gap is wrong, the full-scale range will not work properly.

4. What happens during a sensor failure?
When a NOT OK condition occurs, the signal output drops below 3.6 mA within 100 µs. After the problem is removed, the 990 Vibration Transmitter restores normal output in 2-3 seconds.

5. What is the maximum cable length for the BNC output?
For the Proximitor Sensor Output with BNC connector, the maximum cable distance is 3 meters (10 feet). Longer cables can degrade signal quality.