3500/45 Position Monitor – Bently Nevada™ 4-Channel Rack Module
Series: 3500 Machinery Protection System | Type: Position Monitor
Product Overview
The Bently Nevada 3500/45 is a 4-channel monitor accepting inputs from proximity transducers, RPTs, DC/AC LVDTs, and rotary potentiometers. It conditions signals and compares them against user-programmable alarms. Primary functions: machinery protection and critical operational data for maintenance teams.
Each channel supports: Axial (thrust) Position, Differential Expansion, Standard/Non-standard Single Ramp, Dual Ramp, Complementary Differential Expansion, Case Expansion, and Valve Position. Programmable via 3500 Rack Configuration Software.
Alert & Danger setpoints per channel | Recorder outputs 4–20 mA | Bypass mode | Built-in transducer power supplies
Technical Data
Brand: Bently Nevada | Model: 3500/45 | Series: 3500 Rack Mount
| Inputs | 1 to 4 signal inputs, configurable |
| Power Consumption | 7.7 W (Position I/O), 8.5 W (AC LVDT), 5.6 W (Rotary Pot) |
| Input Impedance | 1 MΩ (DC LVDT) | 10 kΩ (Proximitor/RPT) | 137 kΩ (AC LVDT) | 200 kΩ (Rotary Pot) |
| Sensitivity (Thrust) | 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) |
| Ramp Differential Sensitivity | 0.394 / 0.787 / 3.937 / 7.874 V/mm (10–200 mV/mil) |
| CIDE Sensitivity | 0.394 / 0.787 / 3.937 V/mm (10–100 mV/mil) |
| DC LVDT Case Expansion | 0.05 / 0.08 / 0.10 / 0.18 / 0.20 / 0.22 V/mm (1.25–5.70 V/in) |
| AC LVDT Valve Position Sensitivity | 28.74 / 15.35 / 9.45 / 10.24 / 7.48 / 5.51 / 3.94 / 3.15 mV/V/mm |
| Rotary Potentiometer | 41 mV/degree rotation |
| RPT Valve Position | 140 / 70 / 50 mV/deg rotation |
| Recorder Output | 4–20 mA, proportional to full-scale, 0–600 Ω load, 0.3662 µA/bit, ±0.25% error (room temp) |
| Update Rate | ≤ 100 ms |
| Accuracy (Thrust, DE, CIDE, Case, Valve) | ±0.33% of full-scale typical, ±1% maximum |
| Frequency Response | Direct filter -3 dB @ 1.2 Hz; Gap filter -3 dB @ 0.41 Hz |
| Transducer Power | Proximitor/RPT: -24 Vdc | DC LVDT: +15 Vdc | AC LVDT: 2.3 Vrms 3400 Hz | Rotary Pot: -12.38 Vdc |
| Operating Temperature | -30 °C to +65 °C (-22 °F to +150 °F) |
| Storage Temperature | -40 °C to +85 °C (-40 °F to +185 °F) |
| Humidity | 95% non-condensing |
| LED Indicators | OK, TX/RX, Bypass |
| Voltage Compliance | 0 to +12 Vdc range across load (current output) |
Measured Variables & Diagnostics
- Thrust Position: Direct Gap
- Differential Expansion: Direct Gap
- Ramp Differential: Composite Direct Gap
- CIDE (Complementary): Composite Direct Gap
- Case Expansion: Composite Direct and Position
- Valve Position: Direct and Position
Diagnostic features: continuous comparison against configured alarm setpoints, Bypass mode for maintenance, and individual recorder outputs for trend analysis.
Installation & Compatibility
- Mounting: 3500 Rack compatible (standard 19″ chassis).
- I/O Modules: Internal/External Termination I/O Module supported.
- Compatibility: Works with Proximitor, RPT, DC/AC LVDT, rotary potentiometer transducers.
- Certification: Meets industrial standards for machinery protection (CE, UL, CSA upon request).
- Debug & Maintenance: Front-panel LEDs (OK, TX/RX, Bypass) and software configuration via 3500 Rack Config Software.
Typical Applications
- Steam & gas turbine thrust position monitoring
- Compressor differential expansion and case expansion
- Valve position feedback in critical control loops
- Rotating machinery protection (pumps, fans, generators)
- Complementary differential expansion for large casings
FAQ
Q: Can I use this with AC LVDT sensors?
Yes, AC LVDT inputs are supported with built-in excitation (2.3 Vrms 3400 Hz).
Q: What is the update rate for recorder outputs?
100 ms or less, fast enough for trend monitoring.
Q: Does the module support bypass mode?
Yes, Bypass LED indicates when active, useful during maintenance.
Q: What is the load range for 4–20 mA outputs?
0 to 600 Ω, with voltage compliance 0 to +12 Vdc.
Q: Is the module compatible with obsolete systems?
Yes, supports legacy Bently Nevada 3500 racks and many transducer types.
Why Buy From Oiltech Controls?
- ✓ 15+ years industrial automation spare parts experience
- ✓ Global shipment – FedEx, UPS, DHL express available
- ✓ Tested surplus / refurbished options with verified performance
- ✓ 12-month warranty on all modules
- ✓ Technical verification before shipment (configuration check)
- ✓ Support for obsolete control systems, including Modicon Quantum and legacy Bently racks.
Shipping: FedEx, UPS, DHL – worldwide express.
Inquiries: info@oiltechcontrols.com | +86 158 8020 0923 (WhatsApp)
Packaging: Anti-static, padded box with installation guide (digital).
Copyright © 2026 Oiltech Controls Limited. All rights reserved.
Original Source: https://www.oiltechcontrols.com/
Reviews
There are no reviews yet.