Product details
Product Brief: Bently Nevada 3500/77M Pressure Monitor
The Bently Nevada 3500/77M (Product No. 176449-07) is a high-precision Pressure Monitor for critical machinery protection. It accepts 1 to 4 channels of approved positive voltage transducers. This module delivers accurate cylinder pressure measurement for reciprocating compressors. Designed for harsh environments, it ensures reliable vibration monitoring and machinery protection.
Why Choose This Monitor
- ±0.5% High Accuracy at +25°C (77°F) for precise data
- Measures Discharge, Suction, Max/Min Pressure, Compression Ratio, and Rod Reversal
- Wide Frequency Response: 0 to 5.5 kHz on all channels
- Operating Temperature: -30°C to +65°C (-22°F to +150°F)
- Low Power Consumption: 7.8 Watts at full load
Technical Specifications
- Brand: Bently Nevada
- Model: 3500/77M
- Part Number: 176449-07
- Type: Cylinder Pressure Monitor
- Inputs: 1 to 4 channels, 50 kΩ impedance
- Scale Factor Ranges (mV/psi):
- 95,000 for 100 psia
- 38,000 for 250 psia
- 19,000 for 500 psia
- 9,500 for 1000 psia
- 3,800 for 2500 psia
- 1,900 for 5000 psia
- 950 for 10,000 psia
- Pressure Accuracy: Within ±0.5% full-range (9.5V) @ +25°C; ±1.0% over -30°C to +65°C
- Frequency Response: 0 to 5.5 kHz
- Output Impedance: 550 Ω
- Buffered Output: Inverted, offset by -2.265 Vdc
- Transducer Power Supply: +23.0 ± 0.8 Vdc, 24.5 mA current limiting
- LED Indicators: OK, TX/RX, Bypass
Configuration & Compatibility
- Rack Space: 1 full-height front slot (monitor) + 1 full-height rear slot (I/O)
- I/O Module: Internal/External Termination Cylinder Pressure I/O
- Compatibility: Fully compatible with 3500 rack systems
- Approvals: Manufactured in USA, meets industry standards for industrial automation
Environmental & Physical Data
- Temperature Range (Operation): -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
- Monitor Dimensions: 241.3 x 24.4 x 241.8 mm (9.50 x 0.96 x 9.52 in)
- Monitor Weight: 0.91 kg (2.0 lb)
- I/O Module Dimensions: 241.3 x 24.4 x 99.1 mm (9.50 x 0.96 x 3.90 in)
- I/O Module Weight: 0.20 kg (0.44 lb)
Installation & Maintenance
- Installation: Simple front-slot insertion into 3500 rack. No special tools required.
- Maintenance: Front panel LEDs provide instant status. Buffered coaxial outputs for easy diagnostics.
- Bypass Mode: LED indicates when module is in bypass, simplifying troubleshooting.
Typical Applications
- Reciprocating compressor monitoring
- Cylinder pressure analysis
- Peak rod compression and tension measurement
- Discharge and suction pressure tracking
- Machinery protection in oil, gas, and power plants
Diagnostic Capabilities
- Real-time peak pressure detection
- Degree of rod reversal analysis
- Compression ratio calculation
- Buffered output for external analysis tools
- Continuous self-check with OK LED
Frequently Asked Questions (FAQ)
- What transducers work with the 3500/77M?It accepts Bently Nevada approved positive voltage 3rd-party pressure transducers (psia).
- Can I monitor 4 channels simultaneously?Yes. It supports 1 to 4 channels with independent signal conditioning.
- How do I verify module health?Check the front panel OK LED. It lights green when operating properly.
- Is this module backward compatible?Yes. It fits all standard 3500 racks and works with existing I/O modules.
- What is the typical lead time?Usually ships within 24 hours via Fedex, UPS, or DHL.
- Do you offer technical support?Yes. Contact our team for setup, configuration, or troubleshooting.
Buying Guide & Experience Tips
- Match scale factor to your transducer.Use 95,000 mV/psi for 100 psia sensors. Wrong settings cause inaccurate readings.
- Order spare I/O modules.Rear modules are interchangeable. Keep one in stock to minimize downtime.
- Verify firmware revision.Newer units include enhanced rod reversal algorithms. Ask us for latest version.
- Consider temperature extremes.If ambient exceeds +65°C, use external cooling or relocate rack.
- Use buffered outputs.Connect to oscilloscope or analyzer for advanced diagnostics without interrupting protection.
- We recommend:For 2500 psia applications, order pre-calibrated units. This reduces setup time and errors.
Package List
- 1 x Bently Nevada 3500/77M Pressure Monitor (176449-07)
- 1 x Cylinder Pressure I/O Module (Internal/External Termination)
- Product documentation and quick start guide
- Factory calibration certificate
Warranty & Shipping
- Warranty: 12 months from date of shipment. Covers defects in materials and workmanship.
- Shipping Partners: Fedex, UPS, DHL. Expedited available.
- Global Delivery: Fully tracked and insured.
Ordering & Contact
- Inquiries: sales@powergearx.com
- Phone / WhatsApp: +86 18030005825
- Product Link: View 3500/77M Series
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Original Source: https://www.powergearx.com/
Partner: PLCDCS HUB Limited
Robert Jenkins –
The 3500/77M pressure monitor module was deployed in a chemical processing unit where accurate pressure protection is essential. The module was new, well-packaged, and ready for immediate installation. PowerGearX provided excellent communication and fast shipping to our Louisiana site. In operation, the module has shown consistent performance even under harsh operating conditions. It integrates smoothly with the 3500 system and gives us confidence in our pressure protection strategy. This purchase met all expectations in terms of quality, delivery speed, and technical reliability.