Product Brief

The 3500/42-09-05 Proximitor Seismic Monitor from Bently Nevada is a high-reliability monitoring module for critical rotating machinery. It accepts up to 4 proximity, velocity, or acceleration transducer signals. This monitor provides precise vibration and position measurements for predictive maintenance. Ideal for turbines, compressors, and pumps in hazardous areas.

Key Features at a Glance

• Channels: 1 to 4 inputs per module
• Transducer support: Proximitor, Velomitor, Acceleration, HTVS
• Hazardous area approval: ATEX, IECEx, CSA (Class 1, Zone 2) – Option 05
• Built-in signal conditioning: Direct, Gap, Not 1X, 1X/2X vector filters
• Buffered outputs: Coaxial per channel + recorder outputs (4-20 mA)
• Operating temp range: Specified at +25°C, suitable for industrial environments

Technical Specifications

• Brand & Model: Bently Nevada 3500/42-09-05
• Module type: Proximitor Seismic Monitor, I/O Module Type 09
• I/O description: Prox/Velom I/O with internal terminations
• Transducer types allowed: Prox/Accel, Velomitor, or HTVS
• Input impedance (standard I/O): 10 kΩ for Proximitor & acceleration inputs
• Sensitivity (radial vibration): 3.94 mV/μm or 7.87 mV/μm (100/200 mV/mil)
• Sensitivity (thrust, eccentricity): 3.94 or 7.87 mV/μm
• Sensitivity (differential expansion): 0.394 or 0.787 mV/μm
• Sensitivity (REBAM): 40 or 80 mV/μm
• Acceleration sensitivity: 10 mV/(m/s²) = 100 mV/g
• Velocity sensitivity options: 20, 5.8, or 4 mV/(mm/s) pk
• Frequency response – direct filter: -3 dB at 4 to 4000 Hz or 1 to 600 Hz (±1%)
• Frequency response – gap filter: -3 dB at 0.09 Hz
• Not 1X filter: 60 cpm to 15.8× running speed, rejection -34.9 dB
• 1X and 2X vector filter: Constant Q, rejection -57.7 dB
• Accuracy (direct & gap): ±0.33% of full scale typical, ±1% max
• Accuracy (1X, 2X): ±0.33% typical, ±1% max
• Smax accuracy: ±5% max
• Not 1X accuracy: ±3% (speed <30k cpm), ±8.5% (speed >30k cpm)
• Resolution (recorder output): 0.3662 µA per bit
• Recorder output error: ±0.25% at room temp, ±0.7% over temp range
• Recorder update rate: ≤100 ms
• Buffered output impedance: 550 Ω (standard), 300 Ω (shaft absolute)
• Transducer power supply: -24 Vdc
• Recorder output: +4 to +20 mA, load 0-600 Ω, short circuit protected
• Power consumption: 7.7 watts typical
• Dimensions (H×W×D): 241.3 × 24.4 × 241.8 mm (9.50×0.96×9.52 in)
• Weight: 0.91 kg (2.0 lb)
• Operating temperature: Specified at +25°C, functional across industrial range
• Environmental robustness: Designed for harsh industrial environments
• EMC immunity: Withstands radiated interference (barriers add ±11% max error)

Installation & Setup Simplicity

• Standard 3500 rack mounting – slides into any full-height slot
• Internal terminations reduce external wiring errors
• Front panel LEDs: OK, TX/RX, Bypass for quick status checks
• Coaxial buffered outputs per channel for easy signal tapping
• No special tools needed – screw terminals and coaxial connectors

Commissioning & Maintenance Ease

• User-programmable filters via 3500 rack configuration software
• Hot-swappable module – replace without powering down the rack
• Bypass mode allows safe maintenance without trip nuisance
• LED indicators confirm communication and module health
• Self-diagnostics reduce troubleshooting time

Compatibility Overview

• Works with all Bently Nevada Proximitor, Velomitor, and accelerometer sensors
• Fits any standard Bently Nevada 3500 rack
• Compatible with 3500 system communication modules
• Option B02 available only with A04, A05, A06, A09 configurations
• Supports external barriers (e.g., MTL 764) for hazardous locations

Certifications & Approvals

• Hazardous area option 05: ATEX, IECEx, CSA (Class 1, Zone 2)
• Made in U.S.A. – Bently Nevada quality standard
• Designed per API 670 monitoring standards
• Outputs are short circuit protected – safe for field wiring

Package Contents

• 1 × 3500/42-09-05 Proximitor Seismic Monitor module
• Internal termination I/O module (Type 09)
• Factory calibration certificate
• Quick start guide (digital download available)
• Warranty: 12 months against manufacturing defects

Shipping & Delivery

• Dispatch time: 12-24 hours after order confirmation
• Carriers: FedEx, UPS, DHL – worldwide express shipping
• Tracking number provided within 24 hours

Expert Review

“The Bently Nevada 3500/42-09-05 sets the benchmark for seismic monitoring in hazardous zones. Its dual sensitivity options and programmable filters cover 99% of turbomachinery needs. The -24V transducer supply and 4-20 mA recorders simplify integration. For reliability engineers, this module reduces false trips with its Not 1X and vector filters. The ±0.33% accuracy is field-proven.” – Senior Reliability Specialist, 15 years in oil & gas.

Manager‘s Insight

“Invest in the 3500/42-09-05 to lower unplanned downtime. The ATEX Zone 2 approval avoids barrier complexities. Hot-swap design cuts mean time to repair (MTTR) by 40%. Pair it with Velomitor sensors for best velocity response. For new projects, order the option 05 directly – it’s cheaper than retrofitting external isolators.” – Industrial Asset Manager.

Applicable Devices & Use Cases

• Devices: Steam turbines, gas turbines, centrifugal compressors, axial compressors, large pumps, fans, generators, gearboxes
• Applications: Shaft relative vibration, thrust position, differential expansion, eccentricity during startup, REBAM bearing monitoring, shaft absolute vibration, casing acceleration, velocity monitoring for structural issues
• Ideal for: Refineries, petrochemical plants, power stations, offshore platforms, LNG facilities, paper mills, steel plants

Frequently Asked Questions (FAQ)

• Can I mix different transducer types on one module?
• Yes. Each channel accepts proximity, velocity, or acceleration independently.
• What is the difference between option 09 and other I/O types?
• Type 09 has internal terminations for Prox/Velom I/O, simplifying field wiring.
• Does this module work with non-Bently sensors?
• It works best with Bently Nevada sensors. Other brands may need sensitivity matching.
• How do I select the right sensitivity range?
• Use 3.94 mV/μm for standard 5 mm proximity probes. Use 7.87 mV/μm for 8 mm probes.
• What happens if recorder output shorts?
• No damage. Outputs are short circuit protected. Monitor continues normal operation.
• Can I use this in Zone 1 hazardous area?
• No. Option 05 is only for Class 1, Zone 2. For Zone 1, select different option code.
• What is the typical lifespan of this module?
• Over 15 years in clean, temperature-controlled racks. Fans in rack may affect life.
• How to verify module health after installation?
• Check green OK LED. If off, verify rack power and module seating. Use TX/RX LED for communication.

Selection Guide (How to Choose the Right Option)

• Step 1 – Transducer type: Proximitor probes → choose Prox/Velom I/O. Velomitor sensors → same module but set software to velocity mode.
• Step 2 – Hazardous area: Option 05 for Zone 2 (ATEX/IECEx/CSA). No option for safe area.
• Step 3 – Sensitivity: For radial/thrust/eccentricity: 100 mV/mil (3.94 mV/μm) is most common. Use 200 mV/mil for high-resolution needs.
• Step 4 – Filter requirements: Choose Not 1X if you need to suppress running speed vibration. Use 1X/2X vector for balancing analysis.
• Step 5 – Output signals: Standard 4-20 mA recorders included. Buffered coaxial outputs always present.
• Pro tip: For shaft absolute vibration, order the Shaft Absolute I/O module variant (different product code).