Product Overview
The Bently Nevada 3500/42-01-02 Proximitor Seismic Monitor is a key component in the 3500 series monitoring system, designed to continuously protect rotating machinery by measuring vibration, thrust, and eccentricity. This Industrial Automation Module accepts signals from 1 to 4 proximity, velocity, or acceleration transducers, making it a versatile solution for critical assets. With its hazardous area approval (ATEX / IECEx / CSA Class 1, Zone 2), the 3500/42-01-02 is suitable for demanding environments.
Technical Specifications
The table below summarizes the essential technical parameters for the Bently Nevada 3500/42-01-02. These values are directly from the manufacturer's data and are critical for proper system design.
| Parameter |
Value |
| Input Channels |
1 to 4 (proximity, velocity, or acceleration) |
| Power Consumption |
7.7 watts, typical |
| Input Impedance (Standard I/O) |
10 kΩ (Proximitor and acceleration inputs) |
| Radial Vibration Sensitivity |
3.94 mV/μm (100 mV/mil) or 7.87 mV/μm (200 mV/mil) |
| Thrust Sensitivity |
3.94 mV/μm (100 mV/mil) or 7.87 mV/μm (200 mV/mil) |
| Eccentricity Sensitivity |
3.94 mV/μm (100 mV/mil) or 7.87 mV/μm (200 mV/mil) |
| Differential Expansion Sensitivity |
0.394 mV/μm (10 mV/mil) or 0.787 mV/μm (20 mV/mil) |
| REBAM Sensitivity |
40 mV/μm (1000 mV/mil) or 80 mV/μm (2000 mV/mil) |
| Acceleration Sensitivity |
10 mV/(m/s²) (100 mV/g) |
| Velocity Sensitivity |
20 mV/(mm/s) pk (500 mV/(in/s) pk) or 5.8 mV/(mm/s) pk (145 mV/(in/s) pk) or 4 mV/(mm/s) pk (100 mV/(in/s) pk) |
| Transducer Power Supply |
-24 Vdc |
| Recorder Output |
+4 to +20 mA |
| Buffered Output Impedance |
550 Ω |
| Shaft Absolute Output Impedance |
300 Ω |
| Monitor Module Dimensions (HxWxD) |
241.3 mm x 24.4 mm x 241.8 mm (9.50 in x 0.96 in x 9.52 in) |
| Monitor Module Weight |
0.91 kg (2.0 lb) |
| I/O Module Dimensions (HxWxD) |
241.3 mm x 24.4 mm x 163.1 mm (9.50 in x 0.96 in x 6.42 in) |
| I/O Module Weight |
0.46 kg (1.01 lb) |
Industry Applications
The Bently Nevada 3500/42-01-02 is engineered for reliability in a wide range of industries, including oil and gas, power generation, and petrochemical. For example, in a turbomachinery train, the monitor continuously measures radial vibration and thrust, providing early detection of bearing wear or misalignment. The high sensitivity options (e.g., 7.87 mV/μm) allow precise monitoring of high-speed rotating equipment, while the ATEX/IECEx/CSA approval enables installation in hazardous areas without compromising safety. By integrating this monitor into a 3500 rack, operators gain real-time data that supports predictive maintenance strategies, reducing unplanned downtime.
Installation & Setup Guidance
Proper installation of the 3500/42-01-02 is essential for accurate vibration monitoring. Begin by confirming that the monitor is correctly seated in a 3500 rack slot. Connect the transducer inputs to the appropriate terminals on the I/O module, ensuring polarity matches the sensor wiring. For proximity probes, verify the gap voltage is within the specified range before energizing the monitor. Configure the monitor using the 3500 configuration software, setting each channel's sensitivity and filter options according to your machine's characteristics. Always consult the user manual for detailed wiring diagrams and setup procedures.
Maintenance & Reliability
Routine maintenance of the Bently Nevada 3500/42-01-02 is straightforward. Periodically inspect the front panel LEDs: the OK LED should remain lit, the TX/RX LED should blink during communication, and the Bypass LED should be off during normal operation. Check that all coaxial connectors are clean and tight, as loose connections can introduce noise. Monitor the recorder output for any drift or anomalies, which may indicate a developing sensor issue. By keeping the module clean and operating within specified environmental limits, you can extend its service life and avoid unexpected failures.
Compatibility & Integration
The 3500/42-01-02 is designed to operate within the Bently Nevada 3500 rack system, interfacing with other 3500 modules and the 3500 Rack Configuration Software. It supports a variety of transducers, including Proximitor probes, Velomitor velocity sensors, and accelerometers, as specified in the ordering information. The monitor provides buffered transducer outputs and recorder outputs (4-20 mA) for integration with external diagnostic systems or PLCs. For hazardous area installations, the module's ATEX/IECEx/CSA approval ensures compatibility with appropriate barriers.
Selection Guide & Purchasing Advice
Before purchasing the 3500/42-01-02, verify that your system requires the specific I/O module type (128229-01 Prox/Seismic I/O Module with internal terminations) and the hazardous area approval option (02 = ATEX / IECEx / CSA Class 1, Zone 2). Ensure that the transducer types you plan to connect are supported — note that Seismoprobe Prox/Accel and Velomitor are supported but not recommended. Confirm that the monitor's power consumption (7.7 W typical) is within your rack's power budget. PLC Source PRO offers this genuine Bently Nevada module with fast shipping and expert support, making it a reliable source for your critical spares.