21505-12-40-10-02 | Bently Nevada 80 mils Range 8 mm Probe

Introduction to the Bently Nevada 21505-12-40-10-02

When rotating machinery demands reliable vibration monitoring, the 21505-12-40-10-02 from Bently Nevada provides a proven solution. This proximity probe system is engineered for continuous operation in demanding industrial environments. It offers a calibrated range of 80 mils (2.0 mm), making it suitable for a wide variety of turbomachinery and rotating equipment applications.

The 21505-12-40-10-02 is part of the 7200 proximity transducer system family. It is supplied new and in original factory packing, backed by a 12-month factory warranty. With a total length of 1.0 metre (39 inches), this probe is ready for installation in many standard mounting configurations.

Key Features and Technical Specifications

The 21505-12-40-10-02 offers a set of specifications that ensure accurate and repeatable measurements. The following bullet points summarize the most critical parameters from the datasheet.

• 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), with ±4% accuracy 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 a 50 mils gap (1.27 mm).
• 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).

One distinctive feature is the 8 mm probe diameter, which allows for installation in tighter spaces while maintaining a robust measurement. Additionally, the stainless steel lead armor protects the cable in harsh environments, enhancing long-term reliability.

Applications and Use Cases

The 21505-12-40-10-02 is commonly used for shaft vibration and position monitoring in turbines, compressors, pumps, and electric motors. Its frequency response up to 10 kHz covers the typical vibration frequencies of high-speed rotating machinery. Furthermore, the probe’s corrosion resistance to air, water, lube oil, and certain chemicals makes it suitable for many industrial settings.

In a typical scenario, the probe is mounted near a bearing housing to measure relative shaft vibration. The output signal can be fed into a vibration monitoring system for real-time analysis and alarm generation. By providing early detection of abnormal vibration, this probe helps prevent costly unplanned downtime.

Installation and Setup

Proper installation is essential for accurate readings. The 21505-12-40-10-02 features a 3/8-24 threaded configuration, which is a common standard for proximity probes. When mounting, ensure the probe face is positioned correctly relative to the target surface, typically with an initial gap within the calibrated range.

The total length of 1.0 metre (39 inches) with a tolerance of +0.25 metre / -0.10 metre provides flexibility for routing the cable. The miniature male coaxial connector option (option 02) simplifies connection to extension cables or proximitors. Always follow the manufacturer’s installation manual for specific gap and torque requirements.

Maintenance and Reliability

Regular inspection of the probe and cable is recommended to ensure reliable operation. Check for any physical damage, such as cuts or abrasions on the lead armor. Also, verify that the mounting is secure and that no debris or contamination affects the probe face.

Because the system is designed for continuous duty, it is important to monitor the output signal periodically. If readings drift or become erratic, consult the troubleshooting section of the manual. With proper care, the 21505-12-40-10-02 can provide years of dependable service.

Compatibility and Integration

The 21505-12-40-10-02 is designed to work with Bently Nevada 7200 series proximitors and monitoring systems. It is also compatible with other Bently Nevada vibration monitoring platforms that accept standard proximity probe inputs. The 200 mV/mil scale factor ensures consistent signal levels across different monitoring systems.

For integration, the probe connects to a proximitor, which converts the probe’s impedance change into a voltage signal proportional to displacement. This signal can then be interfaced with PLCs, DCSs, or dedicated vibration monitors. Always verify compatibility with your specific monitoring hardware before installation.

Comparison with Similar Products

Compared to other proximity probes in the 7200 series, the 21505-12-40-10-02 offers a balanced combination of range and resolution. The 80 mils range is suitable for many large rotating machines, while the 200 mV/mil scale factor provides good sensitivity. For applications requiring a longer cable, the 1.0 metre length is a standard option, but other lengths are available.

When compared to probes with smaller diameters, the 8 mm version offers a good compromise between ease of installation and measurement accuracy. The stainless steel lead armor adds durability, which is especially beneficial in harsh environments.

FAQs

Q: What is the calibrated range of the 21505-12-40-10-02?

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

Q: What is the scale factor of this probe?

A: The scale factor is 200 mV/mil (7.87 V/mm), with ±4% accuracy when calibrated as a system.

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: What is the power requirement for the 21505-12-40-10-02?

A: The power requirement is -17.5 Vdc to -26 Vdc at 12 mA maximum consumption.

Q: Does the probe come with a warranty?

A: Yes, it is supplied new with a 12-month factory warranty.

Product Support and Availability

The 21505-12-40-10-02 is available from Petro Auto Tech, an industrial automation parts supplier. It is in stock and ready to ship. For assistance with selection or technical questions, contact Petro Auto Tech for prompt support.