21504-00-08-05-02 | Bently Nevada 8 mm Proximity Probe Vibration Transducer

Introduction to the Bently Nevada 21504-00-08-05-02 Proximity Probe

When machinery vibration threatens uptime, the 21504-00-08-05-02 from Bently Nevada provides reliable measurement. This 8 mm proximity probe is part of the 7200 Proximity Transducer Systems family. It is designed for continuous monitoring of rotating equipment. The probe offers a calibrated range of 80 mils (2.0 mm) with a scale factor of 200 mV/mil. Engineers trust this model for accurate vibration data in harsh industrial environments.

Key Features and Technical Specifications of the 21504-00-08-05-02

• Power: Operates on -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.
• Output: Calibrated range of 80 mils (2.0 mm), starting at approximately 10 mils (0.25 mm) from the 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 (1.27 mm).
• Environmental Limits: Operating temperature for the proximitor is -60°F to +212°F (-51°C to +100°C); probe and extension cable operate from -30°F to +350°F (-34°C to +177°C).
• Corrosion Resistance: Unaffected by direct contact with air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, or DMF.
• Weight: System weight is 1.3 lbs (0.59 kg).

The 8 mm probe diameter and 0.5 metre total length (with +0.13 metre, -0.05 metre tolerance) make it suitable for tight installations. Its unthreaded length is 0 mm, and overall case length is 80 mm. The connector option includes a miniature male coaxial connector.

Applications and Use Cases for the 21504-00-08-05-02

This proximity probe excels in monitoring shaft vibration and position in turbines, compressors, and pumps. For example, in a steam turbine installation, the 21504-00-08-05-02 provides real-time data to prevent catastrophic failure. Its corrosion resistance allows use in chemical processing environments. The wide operating temperature range supports outdoor and high-heat applications. Engineers can integrate it into existing Bently Nevada monitoring systems for seamless data collection.

Installation and Setup Guide

Mount the probe with the specified 318-24 thread configuration. Ensure the gap between the probe face and target is set according to the calibrated range. Use the miniature male coaxial connector for signal transmission. Verify power supply within -17.5 Vdc to -26 Vdc before energizing. Follow the manufacturer's manual for proper alignment and clearance. Always test the system after installation to confirm scale factor accuracy.

Maintenance and Reliability Tips

Regularly inspect the probe and cable for physical damage or contamination. Check the connector for secure fit and corrosion. Monitor the output for drift or noise, which may indicate wear. The probe's robust design minimizes maintenance needs in clean environments. For long-term reliability, verify the operating temperature stays within limits. Contact Bently Nevada or Petro Auto Tech for replacement parts if needed.

Compatibility and Integration

The 21504-00-08-05-02 works with Bently Nevada 7200 Proximitor systems. It is compatible with standard monitoring racks and software. The 200 mV/mil output interfaces directly with vibration analyzers and data acquisition modules. No special adapters are required for most Bently Nevada setups. For third-party systems, confirm input impedance and scaling requirements.

Troubleshooting Common Issues

If output is erratic, check the power supply voltage and connector integrity. Verify the gap is within the calibrated range. Temperature extremes may affect scale factor; refer to the temperature sensitivity spec. For linearity errors, recalibrate the system using the provided tolerance values. If problems persist, consult the official Bently Nevada documentation or contact Petro Auto Tech.

Frequently Asked Questions about the 21504-00-08-05-02

What is the calibrated range of the 21504-00-08-05-02?

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

What power supply does this probe require?

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

What is the frequency response of the 21504-00-08-05-02?

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

Is the probe resistant to corrosion?

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.

What is the total length of the 21504-00-08-05-02?

The total length is 0.5 metre (20 inches), with a tolerance of +0.13 metre, -0.05 metre (+5 inches, -2 inches).

Product Support and Availability

The 21504-00-08-05-02 is available as new and original in factory packing from Petro Auto Tech. It comes with a 12-month factory warranty. In stock and ready to ship, this proximity probe supports your critical vibration monitoring needs. Contact Petro Auto Tech for current lifecycle status and ordering details.