Bently Nevada|3500/72M 176449-08| 4-channel monitor
Bently Nevada 3500/72M 176449-08 Recip Rod Position Monitor
The Bently Nevada 3500/72M is a 4-channel monitor designed to protect reciprocating compressors by measuring rod position, rod drop, and hyper-compressor displacement using proximity transducer inputs.
Features
- Accepts 1–4 proximity probe signals
- Measures dynamic and static position parameters
- Supports user-programmable alert and danger alarm setpoints
- Channels programmed in pairs, allowing two simultaneous functions
- Complies with API 618 for reciprocating compressor monitoring
Technical Specifications
Inputs
- Input Impedance: 10 kΩ
- Nominal Scale Factors:
- Rod Position: 0.79–7.87 mV/µm (20–200 mV/mil)
- Rod Position 2: 3.94–7.87 mV/µm (100–200 mV/mil)
- Rod Drop: 3.94–7.87 mV/µm (100–200 mV/mil)
- Hyper-Compressor: 3.94–7.87 mV/µm (100–200 mV/mil)
Power
- Consumption: 7.7 W (nominal)
Outputs
- Buffered Transducer Outputs: One coaxial connector per channel
- Output Impedance: 510 Ω
- Transducer Power Supply: -24 Vdc
Signal Conditioning
- Accuracy: ±0.33% typical, ±1% max (excluding filters)
- Frequency Response:
- Peak-Peak Filter: Fixed 1 Hz to 600 Hz
- Gap Filter: -3 dB at 0.09 Hz
- Not 1X Filter: Constant Q notch, 34.9 dB rejection
- 1X/2X Vector Filter: Constant Q, 57.7 dB rejection
- Valid Speed Range: 60–2130 cpm
Alarms
- Setpoint Range: 0–100% of full-scale
- Alarm Accuracy: ±0.13% of desired value
- Time Delays:
- Alert: 1–60 sec
- Danger: 0.1 sec nominal or 1–60 sec
Physical
- Monitor Dimensions: 241.3 × 24.4 × 241.8 mm
- Monitor Weight: 0.91 kg
- I/O Module Weights: 0.20 kg (non-barrier), 0.46 kg (barrier)
Environmental
- Operating Temp: -30°C to +65°C (standard), 0°C to +65°C (barrier modules)
- Storage Temp: -40°C to +85°C
- Humidity: 95% non-condensing
Bently Nevada|3500/72M 176449-08| 4-channel monitor



Bently Nevada|3500/72M 176449-08| 4-channel monitor
Bently Nevada 3500/72M 176449-08 Recip Rod Position Monitor
The Bently Nevada 3500/72M is a 4-channel monitor designed to protect reciprocating compressors by measuring rod position, rod drop, and hyper-compressor displacement using proximity transducer inputs.
Features
- Accepts 1–4 proximity probe signals
- Measures dynamic and static position parameters
- Supports user-programmable alert and danger alarm setpoints
- Channels programmed in pairs, allowing two simultaneous functions
- Complies with API 618 for reciprocating compressor monitoring
Technical Specifications
Inputs
- Input Impedance: 10 kΩ
- Nominal Scale Factors:
- Rod Position: 0.79–7.87 mV/µm (20–200 mV/mil)
- Rod Position 2: 3.94–7.87 mV/µm (100–200 mV/mil)
- Rod Drop: 3.94–7.87 mV/µm (100–200 mV/mil)
- Hyper-Compressor: 3.94–7.87 mV/µm (100–200 mV/mil)
Power
- Consumption: 7.7 W (nominal)
Outputs
- Buffered Transducer Outputs: One coaxial connector per channel
- Output Impedance: 510 Ω
- Transducer Power Supply: -24 Vdc
Signal Conditioning
- Accuracy: ±0.33% typical, ±1% max (excluding filters)
- Frequency Response:
- Peak-Peak Filter: Fixed 1 Hz to 600 Hz
- Gap Filter: -3 dB at 0.09 Hz
- Not 1X Filter: Constant Q notch, 34.9 dB rejection
- 1X/2X Vector Filter: Constant Q, 57.7 dB rejection
- Valid Speed Range: 60–2130 cpm
Alarms
- Setpoint Range: 0–100% of full-scale
- Alarm Accuracy: ±0.13% of desired value
- Time Delays:
- Alert: 1–60 sec
- Danger: 0.1 sec nominal or 1–60 sec
Physical
- Monitor Dimensions: 241.3 × 24.4 × 241.8 mm
- Monitor Weight: 0.91 kg
- I/O Module Weights: 0.20 kg (non-barrier), 0.46 kg (barrier)
Environmental
- Operating Temp: -30°C to +65°C (standard), 0°C to +65°C (barrier modules)
- Storage Temp: -40°C to +85°C
- Humidity: 95% non-condensing