21747-045-00 | Bently Nevada 4.5m Extension Cable

Introduction to the Bently Nevada 21747-045-00 Extension Cable

When your machinery monitoring system demands precise signal integrity, the 21747-045-00 from Bently Nevada delivers. This extension cable is engineered to connect a probe with an integral lead to a Proximitor, forming a complete system length of either five or nine meters from probe tip to Proximitor. Designed for industrial environments, it ensures reliable performance in vibration monitoring applications.

Key Features and Technical Specifications

• Model: 21747 - Extension Cable
• Manufacturer: Bently Nevada
• Cable Length: 4.50 meters (177 inches)
• Armor Option: 00 - Without armor
• Power: -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; within ±9.5% including interchangeability errors
• Linearity: Within 0.8 mils (0.02 mm) of a 200 mV/mil straight line if calibrated as a system; within 2.3 mils (0.06 mm) including interchangeability errors
• 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)

These specifications ensure accurate vibration measurement, making the 21747-045-00 a reliable choice for condition monitoring.

Applications and Use Cases

In rotating machinery such as turbines, compressors, and pumps, the 21747-045-00 plays a critical role. It transmits signals from the probe to the Proximitor, enabling continuous vibration monitoring. This helps detect early signs of mechanical wear, misalignment, or bearing faults, preventing unplanned downtime. Furthermore, because probes and cables of the same length are completely interchangeable, maintenance teams can quickly replace components without system recalibration, saving valuable time.

Installation and Setup Guidance

Proper installation is essential for optimal performance. First, verify that the cable length matches your system requirements—the 21747-045-00 provides 4.50 meters (177 inches) of length. Ensure the cable is routed away from high-heat sources and sharp edges to avoid physical damage. When connecting, follow the manufacturer's guidelines for torque and alignment. Since this version comes without armor, consider additional protection in harsh environments. Always refer to the Bently Nevada installation manual for detailed steps.

Maintenance and Reliability Tips

Regular inspection of the cable and its connections helps maintain signal integrity. Check for signs of wear, cuts, or abrasion, especially in areas where the cable bends frequently. Keep the cable away from corrosive chemicals and excessive moisture. The operating temperature range for the probe and extension cable is -30°F to +350°F (-34°C to +177°C), so ensure the environment stays within these limits. By following these practices, you extend the service life of the 21747-045-00 and reduce replacement costs.

Compatibility and Integration

The 21747-045-00 is designed to work seamlessly with Bently Nevada probes and Proximitors. Probes with integral leads of various lengths match average extension cable lengths, ensuring a proper system length. Probes and cables of the same length, along with Proximitors with the same part number, are completely interchangeable. This compatibility simplifies inventory management and system upgrades, as components can be mixed and matched without performance loss.

Troubleshooting Common Issues

If you experience signal loss or erratic readings, first check the cable connections for looseness or corrosion. Verify that the cable length is correct for your system—using an incorrect length can affect calibration. Also, inspect the cable for physical damage, as cuts or kinks can degrade signal quality. If problems persist, consult the Bently Nevada documentation or contact Petro Auto Tech for technical support.

Frequently Asked Questions

Q: What is the length of the 21747-045-00 extension cable?

A: The cable length is 4.50 meters (177 inches).

Q: Does the 21747-045-00 come with armor?

A: No, this model has the armor option 00, meaning it is without armor.

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

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

Q: Is the 21747-045-00 interchangeable with other Bently Nevada cables?

A: Yes, probes and cables of the same length are completely interchangeable.

Product Support and Availability

The 21747-045-00 is available from Petro Auto Tech, an industrial automation parts supplier. It comes new and original in factory packing with a 12-month factory warranty. Contact Petro Auto Tech for current availability and ordering information.