21504-00-56-05-02 | Bently Nevada 8 mm Probe Proximity Vibration

Introduction to the 21504-00-56-05-02

When unplanned downtime threatens production targets, the 21504-00-56-05-02 from Bently Nevada provides the precise vibration data engineers need. This 8 mm probe proximity transducer system monitors rotating machinery with a calibrated range of 80 mils (2.0 mm). It begins measurement at approximately 10 mils (0.25 mm) from the probe face. The device operates on a power supply of -17.5 Vdc to -26 Vdc with a maximum consumption of 12 mA. As part of the 7200 Proximity Transducer Systems family, this model supports critical asset protection in demanding industrial environments.

Key Features and Technical Specifications

• The 21504-00-56-05-02 offers a scale factor of 200 mV/mil (7.87 V/mm) with ±4% accuracy when calibrated as a system.
• Linearity remains within 0.8 mils (0.02 mm) of a 200 mV/mil straight line when calibrated as a system.
• Frequency response spans 0 to 10 kHz (0 to 600,000 cpm) with -5% at 10 kHz.
• Temperature sensitivity is typically -3% change in scale factor at +150°F (+65°C) at 50 mils gap (1.27 mm).
• Operating temperature for the proximitor ranges from -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).
• Relative humidity tolerance reaches 95%, noncondensing.
• System weight is 1.3 lbs (0.59 kg).

The 8 mm probe diameter and 3/8-24 thread configuration ensure straightforward installation. The unthreaded length option is 0 mm, overall case length is 5.6 inches, and total length is 0.5 metre (20 inches) with a tolerance of +0.13 metre, -0.05 metre (+5 inches, -2 inches). The connector option includes a miniature male coaxial connector.

Industry Applications and Use Cases

In petrochemical plants, the 21504-00-56-05-02 monitors compressor shaft vibration to prevent catastrophic failures. Power generation facilities rely on its 200 mV/mil scale factor for turbine bearing condition assessment. Moreover, the corrosion resistance of this 8 mm probe ensures reliable operation when exposed to air, water, lube oil, ammonium hydroxide, sulfuric acid (10%), MEK, or DMF. Consequently, engineers in harsh environments trust this transducer for continuous vibration monitoring.

Installation and Setup Guidance

Mount the probe using the 3/8-24 thread into a pre-drilled hole. Ensure the probe face is positioned at the recommended gap of approximately 10 mils (0.25 mm) from the target surface. Connect the miniature male coaxial connector to the proximitor. Verify the power supply voltage is within -17.5 Vdc to -26 Vdc. Finally, calibrate the system to achieve the specified 200 mV/mil scale factor. Always follow Bently Nevada's installation manual for detailed procedures.

Maintenance and Reliability

Periodically inspect the probe and cable for physical damage or contamination. Check the proximitor's operating temperature to ensure it stays within -60°F to +212°F. The probe itself can withstand temperatures from -30°F to +350°F. Because the system is designed for 95% noncondensing humidity, routine visual checks suffice in most environments. Regular calibration verification helps maintain the ±4% scale factor accuracy. For safety-rated applications, follow the manufacturer's safety manual for inspection intervals.

Frequently Asked Questions about the 21504-00-56-05-02

Q: What is the calibrated range of the 21504-00-56-05-02?

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 Bently Nevada probe?

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

Q: What power supply does the 21504-00-56-05-02 require?

A: It requires -17.5 Vdc to -26 Vdc with a maximum consumption of 12 mA.

Q: What is the frequency response of this proximity transducer?

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?

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

Product Support and Availability

The 21504-00-56-05-02 is available as new and original in factory packing from Petro Auto Tech. It comes with a 12-month factory warranty. For current lifecycle status and ordering details, please contact Petro Auto Tech directly.