Bently Nevada 3500/45 Position Monitor

Advanced Multi-Channel Position Monitoring for Rotating Equipment

The Bently Nevada 3500/45 is a versatile 4-channel position monitor, specifically designed to support various types of position transducers in industrial applications. It accepts inputs from proximity transducers, Rotary Position Transducers (RPTs), DC and AC Linear Variable Differential Transformers (LVDTs), and rotary potentiometers. This flexibility allows the monitor to be used across different systems requiring accurate position feedback.

The monitor processes these inputs and compares the conditioned signals against user-programmable alarm setpoints to ensure reliable operation. It is particularly well-suited for applications that need continuous monitoring of machine position, such as turbines, compressors, and other critical rotating machinery.

Key Technical Specifications

Feature	Specification
Product Type	Position Monitor, 4-Channel
Inputs Supported	Proximity transducers, RPTs, DC/AC LVDTs, rotary potentiometers
Power Supply for Transducers	Proximitor or RPT: 24 Vdc, DC LVDT: +15 Vdc, AC LVDT: 2.3 Vrms, Rotary Potentiometer: -12.38 Vdc
Recorder Output	4-20 mA proportional to full-scale
Voltage Compliance	0 to +12 Vdc across load (0 to 600 Ω)
Resolution	0.3662 µA per bit, ±0.25% error at room temperature, ±0.7% error across temperature range
Update Rate	100 ms or less
Accuracy (Thrust & Differential Expansion)	±0.33% typical, ±1% maximum
Frequency Response (Direct Filter)	3 dB at 1.2 Hz
Frequency Response (Gap Filter)	3 dB at 0.41 Hz
Ramp Differential Expansion Accuracy	Refer to page 13 for details
CIDE Accuracy	±0.33% typical, ±1% maximum
Frequency Response (Direct Filter for CIDE)	3 dB at 1.2 Hz
Frequency Response (Gap Filter for CIDE)	3 dB at 0.41 Hz

Features and Benefits

Versatile Input Compatibility: Accepts a wide range of input signals from proximity transducers, RPTs, LVDTs, and rotary potentiometers, ensuring compatibility with diverse systems.
Precise Output Control: The monitor provides individual recorder values for each channel, except for Ramp and CIDE, with 4-20 mA output proportional to the full-scale reading.
High Accuracy and Precision: Ensures accurate position monitoring with a typical accuracy of ±0.33% for thrust and differential expansion measurements.
Advanced Frequency Response: The monitor features a direct filter with a 3 dB at 1.2 Hz and a gap filter with a 3 dB at 0.41 Hz for enhanced performance.
Resilient Performance: The monitor operates without disruption even when short circuits occur on recorder outputs, ensuring reliable monitoring in harsh conditions.

Applications

The Bently Nevada 3500/45 is ideal for position monitoring in various critical applications, including:

Turbine and Compressor Monitoring: Provides precise position feedback for monitoring the movement of components in turbines and compressors.
Vibration and Thrust Monitoring: Measures axial position and vibration, ensuring machines operate within safe limits.
Differential Expansion Measurements: Used in power plants and industrial settings to measure the expansion between stationary and rotating parts.