990-10-70-03-CN Bently Nevada 990 Transmitter

Bently Nevada 990-10-70-03-CN 990 Vibration Transmitter

Product Introduction

The Bently Nevada 990-10-70-03-CN belongs to the 990 series of vibration transmitters. This device accepts input from a non-contacting 3300 NSv proximity probe and extension cable. Additionally, it converts the probe signal into a standard 4-20 mA output for direct connection to PLCs, DCS systems, or panel meters.

This transmitter offers a full-scale range of 0-10 mils pp (0-250 μm pp) and a 7.0-meter system length. Furthermore, it includes DIN clips and screws for convenient mounting on standard rails. The 990 Vibration Transmitter is an ideal solution for continuous vibration monitoring in pumps, fans, compressors, and other rotating machinery.

Technical Specifications

This section details the core technical parameters of the 990-10-70-03-CN transmitter. The suffix codes precisely define its configuration for accurate ordering.

• Full-Scale Option: 0-10 mils pp (0-250 μm pp) (Suffix 10).

• System Length: 7.0 meters (23.0 feet) (Suffix 70).

• Mounting Option: DIN clips and screws (Suffix 03).

• Agency Approval: Country specific (Suffix CN).

• Input: Accepts 1 non-contacting 3300 NSv proximity probe and extension cable.

• Power Supply: +12 to +35 Vdc at the transmitter terminal.

• Maximum Loop Resistance: 1,000 Ω including cable at 35 Vdc.

• Current Limiting: 23 mA typical.

• 4-20 mA Loop Accuracy: Within ±1.5% over the specified full-scale range.

• Frequency Response: 5 Hz to 6,000 Hz +0, -3 dB.

• Minimum Target Size: 9.5 mm (0.375 in) diameter.

Mechanical and Environmental Parameters

The 990 Vibration Transmitter features a compact and rugged design for industrial environments. The transmitter weighs approximately 0.43 kg (0.9 lbm) and mounts easily using the supplied DIN clips and screws. This mounting option provides secure and reliable installation on standard DIN rails.

For probe gap settings, you must gap the probe between 0.5 and 1.75 mm (20 and 55 mils) from the target to ensure full-scale range coverage. The transmitter features non-interacting external zero and span adjustments, making calibration simple and straightforward. Meanwhile, the NOT OK/signal defeat function forces the output below 3.6 mA within 100 µs after a fault condition occurs, and the output restores within 2-3 seconds after the condition clears.

Electrical Characteristics

The Bently Nevada 990 transmitter offers robust electrical performance for reliable operation. The 4 to 20 mA signal output operates in a 2-wire configuration, simplifying wiring and reducing installation costs. For accuracy, the system maintains ±1.5% over the specified full-scale range, rated from the TEST signal input to the voltage measured across a 250 Ω loop resistance.

In addition, the maximum loop resistance is 1,000 Ω including cable at 35 Vdc, allowing for long cable runs to the control room. The current limiting feature protects the circuit at 23 mA typical. For hazardous area installations, the transmitter supports non-hazardous, Zone 2, or Division 2 locations with a 28 V power supply.

Key Features and Benefits

The 990 Vibration Transmitter offers several distinct advantages for machinery protection applications. First, it accepts a 3300 NSv proximity probe directly, eliminating the need for separate signal conditioners. This simplifies the system design and reduces overall costs.

In addition, the 4-20 mA output interfaces directly with most control systems without additional converters. The non-interacting zero and span adjustments allow for easy field calibration without affecting other settings. Meanwhile, the fast NOT OK response (within 100 µs) ensures that fault conditions are reported immediately to the control system. Consequently, the 990-10-70-03-CN provides reliable, cost-effective vibration monitoring for a wide range of industrial applications.

Installation Guidelines

Proper installation is essential for achieving optimal performance from the 990-10-70-03-CN transmitter.

First, mount the transmitter securely using the DIN clips and screws provided. Ensure the mounting location is clean, dry, and within the specified temperature range. Next, connect the 3300 NSv proximity probe and extension cable to the transmitter input. Then, gap the probe between 0.5 and 1.75 mm (20 and 55 mils) from the target surface.

After that, connect the 4-20 mA loop wiring to the transmitter terminals. Observe the correct polarity and ensure the power supply is within +12 to +35 Vdc. Finally, adjust the zero and span controls to calibrate the output for your specific application requirements.

Packaging List

The 990-10-70-03-CN unit is shipped new and original in factory packaging. The package contains the following items:

• 1 x Bently Nevada 990 Vibration Transmitter.

• 1 x 7.0 m system cable assembly.

• 1 x Set of DIN clips and mounting screws.

• 1 x Installation instruction sheet.

Frequently Asked Questions (FAQ)

1. What probes are compatible with the 990 transmitter?
The 990 Vibration Transmitter accepts a non-contacting 3300 NSv proximity probe and extension cable. Therefore, you should use Bently Nevada 3300 NSv series probes for proper operation.

2. What is the maximum loop resistance for this transmitter?
The maximum loop resistance is 1,000 Ω including cable at 35 Vdc. Meanwhile, you should calculate your total loop resistance to ensure it does not exceed this limit for reliable operation.

3. How do I set the probe gap for this transmitter?
You must gap the probe between 0.5 and 1.75 mm (20 and 55 mils) from the target surface. This range ensures the full-scale output is achieved across the 0-10 mils range.

4. What shipping methods do you use for this item?
We ship this product using major international couriers. The shipping methods are typically Fedex, UPS, or DHL to ensure fast and reliable delivery worldwide.

5. What does the NOT OK signal defeat function do?
The NOT OK function forces the signal output below 3.6 mA within 100 µs after a fault condition occurs. Then, the output restores within 2-3 seconds after the NOT OK condition is removed, providing immediate fault indication to your control system.