The Bently Nevada 21504-000-020-05-02, also cataloged as the 21504-000-020-05-02 Proximity Probes, operates as a dedicated hardware component for non-contacting gap-to-voltage conversion and distance measurement within machinery monitoring systems.

Model Configuration Matrix

• 21504: 7200 Series 8 mm standard mount proximity probe component family
• 000: Minimum unthreaded length option of 0.0 inches
• 020: Case length configuration of 2.0 inches with 3/8-24 thread
• 05: Total system cable length option of 0.5 metre (20 inches)
• 02: Miniature male coaxial connector configuration
• 00: Standard manufacturing revision option

Hardware Specifications

Rotor Dynamics and Gap Voltage Validation

• The transducer system applies eddy-current probe scaling to convert physical gap clearances into proportional voltage outputs.
• Proper operation requires gap voltage validation to ensure the static operating point achieves the target -10 VDC baseline.
• Rotor dynamics analysis depends on high-frequency response characteristics to capture transient vibration and shaft position changes.
• Cross-talk suppression mechanisms prevent mutual electrical interference when multiple probes are installed closely on machinery housings.

Ordering Information

• 1 x 21504-000-020-05-02 Proximity Probe
• 1 x Mounting Locknut
• 1 x Insulating Sleeve

Mechanical Installation Guidelines

• Thread the probe securely into a standard 3/8-24 UNF tapped hole to prevent signal distortions induced by mechanical looseness.
• Handle the fragile 0.5 metre coaxial cable with care, avoiding sharp bends that can damage internal shielding and impedance stability.
• Route signal cabling away from high-voltage power conduits to minimize external electromagnetic coupling.
• Terminate the coaxial shield correctly at the monitoring rack to maintain ground continuity and eliminate noise loops.

Technical FAQ

• What is the linear measuring range of this 7200 series probe?

  The linear measuring range provides 2.0 mm or 80 mils of proportional voltage output.

• What frequency response does the transducer system support?

  The system supports a frequency response from 0 Hz (DC) up to 10 kHz for dynamic and static tracking.

• How should the initial gap voltage be set during installation?

  The gap voltage must be adjusted to align with the -10 VDC target using a voltmeter at the monitor channel.

• Can the 0.5 metre coaxial cable length be modified in the field?

  Field modification alters electrical resonance characteristics and compromises factory calibration accuracy.

• What thread configuration does the probe body utilize?

  The probe uses a standard 3/8-24 UNF external thread profile for mounting into machinery cases.

• Does the probe require an internal power source for operation?

  No, it functions passively and receives excitation current directly from the paired Proximitor sensor.

• What is the primary application for this 8 mm probe model?

  It measures static and dynamic displacement, radial vibration, and shaft position on rotating machinery.

• How is the probe protected against physical damage during routing?

  The coaxial line must be routed through protective metallic conduit to shield against mechanical wear.