Product Overview

3500/42-01-02 is a Proximitor Seismic Monitor from Bently Nevada. It protects rotating machinery by monitoring vibration and position. This module accepts up to 4 transducer signals. It works with proximity, velocity, or acceleration sensors. The 02 suffix adds hazardous area approval for Zone 2.

Key Features

• Channels: 1 to 4 inputs per module
• I/O Type: 01 – Prox/Seismic with internal terminations (PN 128229-01)
• Hazardous Area Approval: 02 = ATEX / IECEx / CSA (Class 1, Zone 2)
• Power Use: 7.7 watts typical
• Input Impedance: 10 kΩ for Proximitor and acceleration inputs
• LED Indicators: OK, TX/RX, Bypass
• Buffered Outputs: Coaxial per channel, short-circuit protected, 550 Ω
• Recorder Outputs: +4 to +20 mA, proportional to full scale, 0 to 600 Ω load
• Transducer Power: -24 Vdc

Technical Specifications

• Brand & Model: Bently Nevada 3500/42-01-02
  • Sensitivity (selectable):
    • Radial Vibration / Thrust / Eccentricity: 3.94 mV/μm (100 mV/mil) or 7.87 mV/μm (200 mV/mil)
    • Differential Expansion: 0.394 mV/μm (10 mV/mil) or 0.787 mV/μm (20 mV/mil)
    • REBAM: 40 mV/μm (1000 mV/mil) or 80 mV/μm (2000 mV/mil)
    • Acceleration: 10 mV/(m/s²) (100 mV/g)
    • Velocity: 20, 5.8, or 4 mV/(mm/s) pk options
  • Frequency Response (key modes):
    • Radial Vibration Direct: -3 dB at 4-4000 Hz or 1-600 Hz (±1%)
    • Radial Vibration Gap: -3 dB at 0.09 Hz
    • Thrust Direct: -3 dB at 1.2 Hz
    • Eccentricity Direct: -3 dB at 15.6 Hz
    • Velocity RMS: 10 to 5500 Hz, -3 dB
  • Accuracy:
    • Direct & Gap: ±0.33% of full scale typical, ±1% max
    • 1X & 2X Vector: ±0.33% typical, ±1% max
    • Smax: ±5% max
  • Resolution (recorder): 0.3662 µA per bit
  • Temperature rating: Specified at +25°C (77°F)
  • Protection: Short circuit protected on all outputs

Dimensions & Weight

• Monitor Module (Main Board): 241.3 mm x 24.4 mm x 241.8 mm (9.50 x 0.96 x 9.52 in), 0.91 kg (2.0 lb)
• I/O Module (Barrier): 241.3 mm x 24.4 mm x 163.1 mm (9.50 x 0.96 x 6.42 in), 0.46 kg (1.01 lb)

Installation & Maintenance

• Installation:
  • Fits standard 3500 rack. Uses one slot (24.4 mm wide).
  • I/O type 01 has internal terminations for easy wiring.
  • Set sensitivity and filters via 3500 Rack Configuration Software.
• Maintenance ease:
  • Front LEDs show OK, communication, and Bypass mode.
  • Hot-swappable. No need to power down the rack.
  • Recorder outputs are short-circuit proof. Safe to test live.
• Compatibility:
  • Works with 3500 rack and Bently Nevada System 1 software.
  • Supports Seismoprobe (best), Velomitor, and proximity probes.

Certification & Packaging

• Hazardous Area Approval: 02 = ATEX, IECEx, CSA (Class 1, Zone 2). Safe for explosive environments.
• Package includes: 1 x 3500/42-01-02 monitor module + 1 x I/O module with internal terminations. No transducers included.
• Warranty: 12 months from shipment. Covers defects.
• Shipping: Same day to 24 hour dispatch. Carriers: FedEx, UPS, DHL.

Expert Review

Manager’s Insight: This 3500/42-01-02 is ideal for Zone 2 areas like refineries and chemical plants. The 4-channel design saves rack space. Use Seismoprobe sensors for best accuracy. Avoid Velomitor in high-EMI zones – accuracy may drop ±11% to ±15%. Overall, a strong choice for critical machinery protection in hazardous locations.

Applicable Equipment & Scenarios

• Equipment: Steam turbines, gas turbines, centrifugal compressors, large pumps, fans, generators.
• Scenarios: Radial vibration, thrust position, differential expansion, shaft eccentricity, REBAM (bearing monitoring), absolute shaft vibration.

Frequently Asked Questions (FAQ)

• What does the 02 approval allow me to do?It lets you install this monitor in Zone 2 hazardous areas (ATEX, IECEx, CSA). Perfect for oil, gas, and chemical plants.
• Can I replace an older 3500/42M with this 3500/42-01-02?Yes, they are mechanically compatible. Just check your rack software version. Update if needed.
• How do I select the right sensitivity for my machine?For radial vibration on most turbines, use 3.94 mV/μm (100 mV/mil). For high vibration, choose 7.87 mV/μm (200 mV/mil).
• What happens if I short the recorder output wires?Nothing. The monitor keeps working. Recorder outputs are fully short-circuit protected.
• Do you offer faster shipping for emergency replacements?Yes. We ship within 12-24 hours. Use FedEx Priority, UPS Worldwide, or DHL Express for next-day delivery.

Selection Guide – How to Pick the Right Model

• • Step 1: Check your hazard area. Need Zone 2? Choose 02 suffix. No hazard? Choose 00.
  • Step 2: Pick I/O type. 01 has internal terminations (easiest). Others use external barriers.
  • Step 3: Match sensitivity to your sensor. Set via software after installation.
  • Step 4: Verify filter needs. Need 1X/2X or Smax? This monitor supports all.
  • Step 5: Order one spare per rack for critical assets. 12-month warranty included.