21504-000-016-10-02 | Bently Nevada 8 mm Probe Proximity Vibration

Introduction to the 21504-000-016-10-02

When machinery vibration threatens uptime, the 21504-000-016-10-02 from Bently Nevada provides accurate proximity measurement. This 8 mm probe is part of the 7200 Proximity Transducer Systems, engineered for continuous monitoring in harsh industrial environments. With a calibrated range of 80 mils (2.0 mm) and a scale factor of 200 mV/mil, it delivers dependable data for predictive maintenance.

Key Features and Technical Specs

• Probe Diameter: 8 mm, standard case construction.
• Thread Type: 3/8-24 threads for secure mounting.
• Total Length: 1.0 metre (39 inches) with tolerance of +.25 metre, -.10 metre.
• Connector: Miniature male coaxial connector for reliable signal transmission.
• Power Input: -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.
• Calibrated Range: 80 mils (2.0 mm), beginning at approximately 10 mils (0.25 mm) from probe face.
• Scale Factor: 200 mV/mil (7.87 V/mm), ±4% when calibrated as a system.
• Linearity: Within 0.8 mils (0.02 mm) of a 200 mV/mil straight line as a system.
• Frequency Response: 0 to 10 kHz (0 to 600,000 cpm); -5% at 10 kHz.
• Temperature Sensitivity: Typically -3% change in scale factor at +150°F (+65°C) at 50 mils gap.

One distinctive spec is the 200 mV/mil scale factor, which provides high-resolution output for early fault detection, helping maintenance engineers catch bearing wear or misalignment before catastrophic failure.

Real-World Applications

In rotating machinery such as turbines, compressors, and pumps, the 21504-000-016-10-02 monitors shaft vibration and position. Its corrosion resistance to air, water, lube oil, and common chemicals makes it suitable for refinery and chemical plant environments. By delivering precise proximity data, it supports condition-based maintenance strategies that reduce unplanned downtime.

Installation Guide

Mount the probe using the 3/8-24 threads, ensuring the unthreaded length option (000 = 00 mm) is correct for your application. The total length of 1.0 metre (39 inches) includes a miniature male coaxial connector for easy integration. Verify the gap setting begins at approximately 10 mils (0.25 mm) from the probe face for optimal linear range. Follow Bently Nevada’s installation manual for proper clearance and cable routing.

Routine Care and Reliability

Inspect the probe and extension cable periodically for physical damage or contamination. The system operates reliably in temperatures from -30°F to +350°F (-34°C to +177°C) for the probe and cable, and up to 95% noncondensing humidity. Regular calibration checks ensure the scale factor remains within ±4% of 200 mV/mil, extending service life and maintaining measurement accuracy.

Compatibility and Integration

The 21504-000-016-10-02 integrates with Bently Nevada 7200 series proximitors and monitoring systems. Its 200 mV/mil output is compatible with standard vibration monitoring modules. For system-level calibration, pair it with a compatible proximitor to achieve ±4% accuracy over the full range.

Troubleshooting Common Issues

If output readings drift or become noisy, check the probe gap and cable connections. Verify the power supply is within -17.5 Vdc to -26 Vdc at 12 mA. For linearity errors beyond 0.8 mils, recalibrate the system as a pair. Always consult the official Bently Nevada documentation for detailed diagnostics.

FAQs about the 21504-000-016-10-02

Q: What is the calibrated range of this probe?

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 21504-000-016-10-02 require?

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

Q: What is the frequency response of this proximity probe?

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

Q: What thread size does the probe use?

A: The probe uses 3/8-24 threads for mounting.

Q: Is the 21504-000-016-10-02 resistant to chemicals?

A: Yes, for 8 mm probes, operation is not affected by direct contact with air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, or DMF.

Product Support and Availability

The 21504-000-016-10-02 is available as new and original in factory packing from Petro Auto Tech. Please verify current lifecycle status and availability with Petro Auto Tech before ordering.