The Bently Nevada 21000-00-00-15-085-03-02, also cataloged as the 21000 Proximity Probe Housing Assembly, operates as a dedicated hardware component for mechanical environmental protection of displacement transducers within machine monitoring platforms.

Model Configuration Suffixes

• 21000: Base model series
• 00-00: Probe and cable requirement null
• 15: Housing length configuration
• 085: Physical dimensions in 0.1 in increments
• 03: Accessory kit (3/4-14 NPT plug, reducer, and cable grip)
• 02: 3/4-14 NPT process connection

Hardware Specifications

Mechanical Protection & Transducer Dynamics

Housing assemblies ensure the longevity of eddy-current probe installations by isolating sensors from industrial environmental hazards. Proper application requires that the probe tip remains centered relative to the target to maintain the validity of -10 VDC gap voltage targets. The assembly facilitates stable rotor dynamics monitoring by providing rigid support, thereby preventing signal noise induced by mechanical oscillation of the mounting interface. Cross-talk suppression is maintained by ensuring proper orientation during the final tightening of the NPT process connection.

Ordering Info

• 1 21000-00-00-15-085-03-02 Housing Assembly
• 1 3/4-14 NPT plug
• 1 3/4-14 to 1/2-14 NPT reducer
• 1 Cable seal grip with associated grommets (1/8 to 3/8 inches)

Installation Procedures

• Process Connection: Thread the 3/4-14 NPT base into the machine casing using an approved pipe sealant to prevent fluid leakage.
• Cable Sealing: Select the appropriate grommet size from the included kit to ensure the cable grip provides a liquid-tight seal around the coaxial cable jacket.
• Structural Integrity: Ensure the assembly is tightened to prevent loosening from machine vibration. Use the included reducer if the signal cabling requires a 1/2-14 NPT interface.
• Alignment: Verify that the probe, once inserted, remains parallel to the shaft center line to avoid measurement errors in proximity data.

Technical Inquiry & Operational FAQ

• Can this housing be used for non-Bently Nevada probes?

  The mechanical threads are standard, but the internal volume and cable sealing integrity are optimized for Bently Nevada 3300/3500 series proximity probes.

• Does the housing affect signal frequency response?

  No. As a passive mechanical housing, it has no impact on the frequency response of the internal displacement transducer.

• What is the purpose of the included reducer?

  The reducer allows for transition between the 3/4-14 NPT housing port and 1/2-14 NPT conduit or cabling hardware.

• Is the seal grip rated for hazardous areas?

  The seal grip provides environmental ingress protection; verify the specific Ex-rating of the overall installation to ensure compliance with zone requirements.

• Can the grommets be reused?

  Grommets should be inspected for compression set; if the seal material is hardened or deformed, it must be replaced to maintain IP rating.

• Why is the NPT thread standard used?

  NPT threads provide a tapered seal necessary for high-pressure machine casings, preventing oil or process fluid leakage at the sensor mount.

• How does the weight affect mounting stability?

  The 1.08 kg mass requires a rigid mounting bracket to prevent resonant frequencies that could introduce artifacts into the vibration measurement.

• Is the cable grip sufficient for shielded cable?

  The grip is designed to compress onto the outer jacket without damaging the internal shielding or the coaxial dielectric.