21508-02-12-50-02 | Bently Nevada 5m Cable 8mm Probe Proximity Vibration

Introduction to the 21508-02-12-50-02

When a rotating machine begins to vibrate unexpectedly, the 21508-02-12-50-02 from Bently Nevada provides the precise measurement needed to diagnose the issue. This proximity probe is engineered for continuous vibration monitoring in industrial environments. As part of the 7200 Proximity Transducer Systems, it offers reliable performance for critical machinery protection.

The 21508-02-12-50-02 is a new and original unit in factory packing, backed by a 12-month factory warranty. Its compact 8 mm diameter design fits into tight mounting spaces, while the 5-meter cable (195 inches) provides flexible installation options. With a total cable length tolerance of +0.6 meter/-0.5 meter, you can plan your routing with confidence.

Key Features and Technical Specifications

The 21508-02-12-50-02 delivers accurate vibration data through several key specifications:

• Calibrated Range: 80 mils (2.0 mm), beginning 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 (system calibrated).
• Frequency Response: 0 to 10 kHz (0 to 600,000 cpm), -5% at 10 kHz.
• Power Requirement: -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.
• 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: Up to 95%, noncondensing.
• System Weight: 1.3 lbs (0.59 kg).

The temperature sensitivity is typically -3% change in scale factor at +150°F (+65°C) at a 50 mils gap (1.27 mm). This means you can trust the readings even in thermally challenging environments.

Real-World Applications

The 21508-02-12-50-02 is ideal for monitoring shaft vibration in turbines, compressors, pumps, and other rotating equipment. In a typical scenario, a plant engineer notices increased vibration on a critical pump. By installing this proximity probe, they can continuously track shaft displacement and detect early signs of bearing wear or imbalance. Consequently, maintenance teams can schedule repairs before a catastrophic failure occurs, reducing downtime and saving costs.

Furthermore, the probe's corrosion resistance to air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, and DMF makes it suitable for harsh industrial environments. Whether in a refinery or a chemical plant, this probe delivers reliable data.

Installation and Setup

Proper installation is crucial for accurate readings. The 21508-02-12-50-02 features a 3/8-24 thread for mounting. Ensure the probe face is positioned correctly relative to the shaft, following the manufacturer's guidelines. The miniature male coaxial connector (option 02) simplifies wiring. For best results, calibrate the system as a whole to achieve the ±4% scale factor accuracy.

When routing the 5-meter cable, avoid sharp bends and excessive strain. Use appropriate cable supports to maintain the integrity of the connection. Always verify the power supply is within the specified range of -17.5 Vdc to -26 Vdc to prevent damage.

Maintenance and Reliability

Regular inspection of the probe and cable is essential for long-term reliability. Check for physical damage, loose connections, and signs of corrosion. Because the probe operates in harsh environments, periodic cleaning may be necessary, but always follow the manufacturer's recommendations. The 12-month factory warranty provides peace of mind, and Bently Nevada's reputation ensures dependable performance.

By investing in the 21508-02-12-50-02, you reduce the risk of unexpected machine failures. Early detection of vibration anomalies allows for planned maintenance, which is more cost-effective than emergency repairs. Therefore, this probe contributes to lower overall operational costs.

Compatibility and Integration

The 21508-02-12-50-02 is part of the 7200 Proximity Transducer Systems, designed to work seamlessly with Bently Nevada monitors. It outputs a 200 mV/mil signal, which is standard for many vibration monitoring systems. However, for specific compatibility with your existing equipment, consult the official documentation or contact Petro Auto Tech for guidance.

Troubleshooting Common Issues

If you experience erratic readings, first check the power supply voltage and ensure it is within the specified range. Also, verify that the probe tip is clean and free from debris. In addition, inspect the cable for any breaks or shorts. If the problem persists, refer to the official Bently Nevada manual or reach out to Petro Auto Tech for technical support.

FAQ about the 21508-02-12-50-02

Q: What is the calibrated range of the 21508-02-12-50-02?

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

Q: What power supply does the 21508-02-12-50-02 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), with -5% at 10 kHz.

Q: What is the operating temperature range for the probe and extension cable?

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

Q: Is the 21508-02-12-50-02 suitable for corrosive environments?

A: Yes, the 8 mm probe is resistant to air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, and DMF.

Product Support and Availability

The 21508-02-12-50-02 is available through Petro Auto Tech, an industrial automation parts supplier. As a new and original unit, it comes with a 12-month factory warranty. Contact Petro Auto Tech to confirm current stock and lead times. Please verify the lifecycle status of this product before ordering, as availability may vary.