Bently Nevada 990-04-70-03-00 Vibration Transmitter

Bently Nevada 990-04-70-03-00 Vibration Transmitter

Product Introduction

The Bently Nevada 990-04-70-03-00 is a high-performance 2-wire vibration transmitter. It continuously monitors rotating machinery like turbines, compressors, and pumps. This model accepts input from a single 3300 NSv proximity probe. It translates shaft vibration into a proportional 4-20 mA signal for easy system integration. Its compact design and robust construction make it suitable for various industrial applications. Specifically, this version offers a 0-4 mils range and a 7.0-meter cable length.

Key Technical Specifications

This section outlines the essential parameters of the Bently Nevada 990 transmitter. These specifications guide proper application and ensure reliable operation.

• Input: The unit accepts one non-contacting 3300 NSv Proximity Probe along with its matching extension cable.

• Power Supply: It requires a DC input voltage between +12 and +35 Vdc applied at the transmitter terminal.

• Signal Output: It delivers a standard 4 to 20 mAdc signal across its specified full-scale range. This uses a 2-wire configuration for simplicity.

• Loop Accuracy: The 990-04-70-03-00 maintains loop accuracy within ±1.5%. Bently Nevada rates this from the TEST signal input across a 250 Ω load. This error is additional to the Prox Out Incremental Scale Factor.

• Frequency Response: The unit captures vibration frequencies from 5 Hz to 6,000 Hz (+0, 3 dB). This covers a wide spectrum of machinery speeds.

• Current Limiting: The typical current limiting is set at 23 mA. This protects the loop wiring and connected instruments from overcurrent faults.

• NOT OK/Signal Defeat: The output drops below 3.6 mA within 100 µs of a Not OK condition. It automatically restores within 2-3 seconds after the fault clears.

Mechanical and Environmental Specifications

The physical attributes and environmental limits are crucial for installation. The 990 Vibration Transmitter is built for longevity in harsh settings.

• Transmitter Weight: It weighs only 0.43 kg (0.9 lbm). This lightweight design simplifies mounting and reduces stress on the mounting hardware.

• Mounting Option: The specific 03 option includes DIN clips and screws for secure and standardized rail mounting.

• Minimum Target Size: The probe requires a minimum target size of 9.5 mm (0.375 in) in diameter for accurate measurement.

• Probe Gap: You must gap the probe between 0.5 and 1.75 mm (20 and 55 mils) from the target. This ensures the full-scale range is achieved.

• Leadwire Length: The maximum cable distance for the Proximitor Sensor Output (BNC connector) is 3 meters (10 feet).

• Hazardous Area: This model is suitable for Non-Hazardous, Zone 2, or Div 2 hazardous area locations.

Installation and Connection Guide

Proper installation is key for the Bently Nevada 990-04-70-03-00 to function correctly. Follow these guidelines for a successful setup.

First, securely mount the transmitter using the provided DIN clips and screws. Ensure the mounting surface is stable and free from excessive vibration. Next, connect the 3300 NSv proximity probe and its extension cable to the input. Subsequently, wire the power supply to the transmitter terminals. A +12 to +35 Vdc source is mandatory.

After that, wire the 4-20 mA loop. The maximum loop resistance must not exceed 1,000 Ω at 35 Vdc. This includes all cable resistance. Finally, set the probe gap correctly. Use the non-interacting external adjustments for zero and span. This will ensure accurate measurement across the specified 0-4 mils range.

Packaging and Delivery

Your order will be carefully packaged to prevent damage during transit. All items are shipped from our warehouse promptly.

Packaging List:

• 1 x Bently Nevada 990-04-70-03-00 Vibration Transmitter

• 1 x DIN clip and screw mounting kit

• 1 x Installation guide (quick start)

Shipping: We use major couriers for reliable worldwide delivery.

• Fedex

• UPS

• DHL

Frequently Asked Questions (FAQ)

1. What is the difference between the 990-04-70-03-00 and other 990 models?
This 990-04-70-03-00 features a 0-4 mils full-scale range and a 7.0-meter system length. It also has the '00' approval option, meaning no specific agency approvals are required.

2. Can I use this transmitter with a 3300 XL probe instead?
The 990 Vibration Transmitter is specifically calibrated for the 3300 NSv proximity probe. Using a different probe model may result in inaccurate readings.

3. What does the 'System Length' option '70' mean?
The '70' in the model number 990-04-70-03-00 specifies a system length of 7.0 meters (23.0 feet). This refers to the total length of the probe and extension cable system.

4. How do I test the loop without running the machine?
You can use the TEST signal input on the transmitter. Bently Nevada rates the accuracy from this TEST input to the voltage measured across a 250 Ω loop resistance.

5. Is the 990-04-70-03-00 suitable for use in explosive atmospheres?
Yes, this model is suitable for Non-Hazardous, Zone 2, or Div 2 hazardous area locations. However, because it has the '00' approval option, it does not carry specific regional certifications.