Product Overview

The 990-05-70-01-00 is an integrated signal conditioning transmitter engineered to provide a simplified, loop-powered solution for machinery vibration monitoring. This Bently Nevada 990 Series device functions as a specialized interface that converts raw eddy current signals from a proximity probe into a standardized 4 to 20 mA analog output. By consolidating the Proximitor sensor and transmitter into a single housing, it allows for direct communication with Programmable Logic Controllers (PLCs), Distributed Control Systems (DCS), and other industrial plant controllers. This configuration is specifically calibrated for a 5.0-meter system length and is designed to interface with the 3300 NSv (Narrow Side-view) proximity transducer system, making it an essential component for Turbine Supervisory Instrumentation (TSI).

Hardware Parameters and Technical Specifications

Constructed for high-density industrial applications, the 990-05-70-01-00 provides precise signal conversion with a focus on ease of installation and long-term stability.

• Model Number 991-05-70-01-00

• Transducer Input 3300 NSv Proximity Probe and Extension Cable

• Total System Length 5.0 Meters (Option -05)

• Full-Scale Measurement 0 to 125 µm (5.0 mils) peak-to-peak (Option -70)

• Output Signal 4 to 20 mA DC (Proportional to vibration amplitude)

• Mounting Configuration 35 mm DIN-rail clips (Option -01)

• Approval Rating Standard (Non-hazardous) or General Purpose (Option -00)

• Loop Voltage Requires +12 to +35 Vdc input

• Diagnostic Port Coaxial BNC connector for raw dynamic signal analysis (buffered)

• Adjustment Controls Accessible Zero and Span potentiometers for loop calibration

Industrial Applications

The 990-05-70-01-00 is the primary choice for Original Equipment Manufacturers (OEMs) of centrifugal air compressors, high-speed motors, and industrial pumps where installation space is restricted. Because it utilizes the 3300 NSv probe, it is uniquely suited for monitoring radial vibration in small bearing housings where a larger 8mm probe would suffer from side-view interference.

By providing a continuous 4 to 20 mA signal, it enables plant operators to trend vibration levels over time and trigger automated alarm or shutdown sequences if vibration exceeds safety thresholds. The inclusion of a buffered diagnostic output allows maintenance engineers to perform frequency spectrum analysis using portable data collectors without disrupting the primary protection loop, facilitating a comprehensive predictive maintenance strategy for critical rotating assets.