Technical Specifications

FAQ

1. What is the main purpose of the Bently Nevada 21505-000-012-05-02 armored probe?

This probe is designed for continuous, non-contact monitoring of rotating machinery, with enhanced mechanical protection due to its armored cable construction. It is used to measure shaft vibration, radial displacement, and axial position in real time. The armored design makes it especially suitable for harsh environments where standard probe cables may be exposed to mechanical wear, vibration, or physical damage. It ensures stable signal transmission for critical machinery protection and condition monitoring applications.

2. What advantage does the armored design provide?

The armored structure significantly improves mechanical durability and resistance to external damage. It protects the probe cable from abrasion, impact, bending stress, and accidental contact with surrounding equipment. This is particularly important in industrial environments with high vibration, rotating components, or tight installation spaces. The added protection increases service life and reduces the risk of signal failure caused by cable damage.

3. How does the probe measure shaft vibration and displacement?

The probe uses the eddy current principle. A high-frequency electromagnetic field is generated at the probe tip. When a conductive target such as a steel shaft approaches, eddy currents are induced on the surface, changing the probe’s electrical characteristics. These changes are converted into a proportional voltage signal that reflects the distance between the probe and the shaft, enabling precise measurement of vibration and displacement without physical contact.

4. What types of machinery typically use this probe?

This probe is commonly used in critical rotating machinery such as steam turbines, gas turbines, centrifugal compressors, industrial pumps, electric motors, and gearboxes. These machines require continuous monitoring of shaft behavior to detect early signs of imbalance, misalignment, bearing wear, or rotor instability. The armored design makes it especially suitable for heavy-duty industrial environments.

5. What type of output signal does the probe provide?

The probe provides a continuous analog voltage signal that varies in proportion to the distance between the probe tip and the shaft surface. This signal is processed by a compatible monitoring system and converted into engineering parameters such as vibration amplitude, shaft displacement, and axial position. These values are used for trending, alarm generation, and protection logic.

6. Is this probe suitable for harsh industrial environments?

Yes, it is specifically designed for demanding industrial conditions. The armored cable structure, combined with industrial-grade shielding, provides strong resistance against vibration, mechanical stress, and electromagnetic interference. This ensures stable performance even in environments with high-speed rotating machinery and continuous operational loads.

7. Does the probe require calibration after installation?

Yes, calibration is required after installation to ensure accurate measurement. The calibration process establishes the correct relationship between the output signal and the actual physical gap between the probe and the shaft. Proper calibration ensures reliable vibration and displacement readings, which are critical for accurate machine condition assessment.

8. What maintenance practices are recommended for this probe?

Recommended maintenance includes periodic inspection of cable integrity, especially the armored section, to ensure there is no physical damage or excessive wear. The probe mounting should be checked for stability, and the probe tip area should be kept clean to avoid contamination from oil, dust, or debris. Signal stability should also be monitored to detect early signs of connection or installation issues.