21504-08-32-10-02 | Bently Nevada 8 mm Probe Proximity Vibration Transducer

What Is the Bently Nevada 21504-08-32-10-02?

When vibration monitoring demands precision and durability, the 21504-08-32-10-02 from Bently Nevada provides a robust solution. This 8 mm probe proximity transducer system is engineered for continuous measurement of shaft vibration and position in rotating machinery. With a calibrated range of 80 mils (2.0 mm) and a scale factor of 200 mV/mil (7.87 V/mm), it delivers accurate data for predictive maintenance. The system operates on a power supply of -17.5 Vdc to -26 Vdc at 12 mA maximum consumption, ensuring stable performance in demanding industrial environments.

Key Features & Technical Specs

• Calibrated Range: 80 mils (2.0 mm) begins at approximately 10 mils (0.25 mm) from the probe face.
• Scale Factor: 200 mV/mil (7.87 V/mm) with ±4% accuracy when calibrated as a system.
• Linearity: Within 0.8 mils (0.02 mm) of a 200 mV/mil straight line when calibrated as a system.
• Frequency Response: 0 to 10 kHz (0 to 600,000 cpm); -5% at 10 kHz (600,000 cpm).
• Temperature Sensitivity: Typically -3% change in scale factor at +150°F (+65°C) at 50 mils gap (1.27 mm).
• Operating Temperature (Proximitor): -60°F to +212°F (-51°C to +100°C).
• Operating Temperature (Probe and Extension Cable): -30°F to +350°F (-34°C to +177°C).
• Relative Humidity: To 95%, noncondensing.
• System Weight: 1.3 lbs (0.59 kg).

One distinctive spec is the frequency response up to 10 kHz, which covers high-speed machinery vibrations common in turbines and compressors. This ensures early detection of developing faults.

Real-World Applications

In power generation and oil and gas facilities, the 21504-08-32-10-02 monitors shaft vibration and position on critical rotating equipment. For example, it helps prevent unplanned downtime in steam turbines by providing real-time data on rotor dynamics. Its corrosion resistance to air, water, lube oil, and several chemicals makes it suitable for harsh environments. Moreover, the system's linearity within 0.8 mils ensures reliable trend analysis for condition-based maintenance programs.

Installation Guide

Mount the probe with a 3/8-24 thread configuration and ensure the unthreaded length is 80 mm. The overall case length is 3.2 inches, and the total cable length is 1.0 meter (39 inches) with a tolerance of +0.25 meter, -0.10 meter. Connect using the miniature male coaxial connector option. Verify the gap voltage at installation to ensure the probe face is within the calibrated range. Follow Bently Nevada's manual for proper alignment and torque specifications.

Routine Care & Reliability

Inspect the probe and cable periodically for physical damage or contamination. The system's operating temperature range from -60°F to +212°F for the proximitor and -30°F to +350°F for the probe ensures reliable operation in extreme conditions. Regular calibration checks, as per manufacturer guidelines, maintain measurement accuracy. The 12-month factory warranty provides added assurance of quality.

Integration Guide

The 21504-08-32-10-02 integrates seamlessly with Bently Nevada 7200 series monitoring systems. It outputs a 200 mV/mil signal compatible with standard vibration monitoring modules. No additional protocols are required for basic operation. For system-level integration, consult Bently Nevada documentation to ensure proper configuration with existing machinery protection systems.

Troubleshooting Common Issues

If the output signal drifts, check the gap voltage and ensure the probe face is clean. Temperature sensitivity of typically -3% at +150°F can cause scale factor changes; compensate by calibrating at operating temperature. For linearity errors beyond 0.8 mils, verify the probe is not contacting the shaft. If frequency response drops below 10 kHz, inspect the cable and connectors for damage. Always refer to the Bently Nevada manual for detailed diagnostics.

FAQs about 21504-08-32-10-02

Q: What is the calibrated range of the 21504-08-32-10-02?

A: The calibrated range is 80 mils (2.0 mm), beginning at approximately 10 mils (0.25 mm) from the probe face.

Q: What power supply does the 21504-08-32-10-02 require?

A: It requires -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.

Q: What is the frequency response of this probe?

A: The frequency response is 0 to 10 kHz (0 to 600,000 cpm); -5% at 10 kHz (600,000 cpm).

Q: What is the operating temperature range for the probe?

A: The probe and extension cable operate from -30°F to +350°F (-34°C to +177°C).

Q: What is the scale factor accuracy?

A: The scale factor is 200 mV/mil (7.87 V/mm) with ±4% accuracy when calibrated as a system.

Product Support & Availability

The Bently Nevada 21504-08-32-10-02 is in stock and ready to ship from Petro Auto Tech. Contact our team for current lead times and bulk pricing. We provide original factory-packed units with a 12-month warranty.