21504-30-60-05-02 | Bently Nevada 8mm Proximity Probe

Introduction to the Bently Nevada 21504-30-60-05-02

When rotating machinery vibration threatens uptime, the 21504-30-60-05-02 from Bently Nevada provides precise, real-time measurement. This proximity probe is part of the 7200 series, engineered for reliable performance in demanding industrial environments.

With a calibrated range of 80 mils (2.0 mm) and a scale factor of 200 mV/mil (7.87 V/mm), this probe delivers accurate data for condition monitoring and protection systems. Its robust design ensures long-term stability, reducing unplanned downtime.

Key Features and Technical Specifications

• Model: 21504-30-60-05-02, Bently Nevada 7200 Proximity Transducer System.
• Probe Diameter: 8 mm with standard case configuration and 3/8-24 threads.
• Total Length: 0.5 metre (20 inches) with tolerance +0.13 metre, -0.05 metre (+5 inches, -2 inches).
• Connector: With miniature male coaxial connector.
• Power Input: -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.
• Calibrated Range: 80 mils (2.0 mm), begins 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 when calibrated 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).
• Operating Temperature: Proximitor: -60°F to +212°F (-51°C to +100°C); Probe and Extension Cable: -30°F to +350°F (-34°C to +177°C).
• Relative Humidity: Up to 95%, noncondensing.
• System Weight: 1.3 lbs (0.59 kg).

One distinctive feature is the 8 mm probe diameter, which allows installation in tight spaces while maintaining high accuracy. This makes the 21504-30-60-05-02 ideal for applications where access is limited.

Applications and Use Cases

The 21504-30-60-05-02 is commonly used in turbomachinery, pumps, compressors, and motors to monitor shaft vibration and position. Its frequency response covers up to 10 kHz, making it suitable for high-speed rotating equipment.

In addition, the probe's corrosion resistance to air, water, lube oil, and certain chemicals ensures reliable operation in harsh environments. Consequently, it is a preferred choice for oil and gas, power generation, and chemical processing facilities.

Furthermore, the calibrated range and linearity specifications support accurate trend analysis, enabling predictive maintenance strategies that reduce costly failures.

Installation and Setup

Proper installation is critical for optimal performance. First, ensure the probe face is positioned within the recommended gap of approximately 10 mils (0.25 mm) from the target surface. Then, tighten the 3/8-24 threads securely, but avoid over-torquing.

Next, connect the miniature male coaxial connector to the extension cable, ensuring a clean, secure fit. Finally, verify the power supply meets the -17.5 Vdc to -26 Vdc requirement at 12 mA maximum consumption. Always follow the manufacturer's installation manual for detailed guidance.

Maintenance and Reliability

Regular inspection of the probe and cable is essential to maintain measurement accuracy. Check for physical damage, such as scratches or bends, that could affect the gap or signal integrity.

Additionally, keep the probe face clean and free from debris, as contamination can alter the gap reading. Environmental factors like temperature and humidity are within specified limits, so the probe should operate reliably under normal conditions.

By following a routine maintenance schedule, you can extend the service life of the 21504-30-60-05-02 and avoid unexpected downtime.

Comparison with Similar Probes

Compared to other 8 mm proximity probes in the 7200 series, the 21504-30-60-05-02 offers a calibrated range of 80 mils (2.0 mm) and a scale factor of 200 mV/mil. Some models may have different unthreaded lengths or overall case lengths, but the sensing characteristics remain consistent.

For instance, a probe with a longer unthreaded length might be used in deeper installations, while the 21504-30-60-05-02's 3.0-inch unthreaded length suits standard mounting. The 6.0-inch overall case length provides adequate reach for many applications.

Ultimately, the choice depends on your specific mounting requirements and target gap. The 21504-30-60-05-02 balances performance and flexibility.

Common Questions About the 21504-30-60-05-02

What is the calibrated range of this probe?

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

What power supply does the 21504-30-60-05-02 need?

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

What is the frequency response?

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

Can this probe withstand harsh environments?

Yes, it operates in temperatures from -30°F to +350°F (-34°C to +177°C) for the probe and cable, and up to 95% relative humidity.

Availability and Support

The Bently Nevada 21504-30-60-05-02 is available as new and original in factory packing, backed by a 12-month factory warranty. Petro Auto Tech is your trusted source for this part, ensuring genuine quality and reliable delivery.

For further assistance, contact Petro Auto Tech to confirm availability and lead times. Our team is ready to support your industrial automation needs.