Bently Nevada 21747-080-00 7200 Series Extension Cable Datasheet

Bently Nevada 21747-080-00 Proximitor Extension Cable

The Bently Nevada 21747-080-00, also cataloged as the 21747-080-00 Proximitor Extension Cable, operates as a dedicated hardware component for signal transmission between a proximity probe and the monitoring system. This cable maintains specific electrical impedance profiles to ensure signal integrity within rotating machinery protection platforms.

Hardware Specifications

Mechanical Monitoring and TSI Characteristics

The 21747-080-00 functions as a passive link within a 7200-series eddy-current measurement chain. Proper system calibration necessitates maintaining the factory-defined impedance match to prevent measurement errors. When configuring these circuits, technicians must verify gap voltage targets typically set at -10 VDC at the monitor input. Furthermore, the cable geometry facilitates high-frequency signal propagation required for accurate rotor dynamics analysis. Installers must minimize cable coiling near high-voltage conduits to suppress signal cross-talk, ensuring that the induced noise floor remains below the thresholds required for vibration displacement monitoring.

Frequently Asked Questions

Q: Does the cable length affect the Proximitor system calibration?

A: Yes. The 8-meter length is factory-calibrated for specific impedance characteristics. Replacing a cable of a different length requires a recalibration of the probe-to-monitor loop to maintain accuracy.

Q: Can this cable be used in high-vibration machinery?

A: Yes. The cable design withstands mechanical stress typical of turbine decks and compressor skids; however, installers must secure the cable using standard clamps to prevent fatigue-induced conductor breakage.

Q: What precautions are necessary for the connectors?

A: Keep the factory-terminated connectors clean and free of moisture. Apply a small amount of non-conductive electrical contact cleaner if oxidation occurs during maintenance, and verify that the locking collars are fully engaged.

Field Installation Guidelines

1. Routing: Route the extension cable through rigid or flexible conduit to protect the polymer jacket from sharp edges and abrasive surfaces.
2. Grounding: Maintain the continuity of the shield and ensure that the monitoring system chassis provides a low-impedance ground reference to mitigate electromagnetic interference.
3. Termination: Align the keyed connectors carefully before tightening the coupling nut. Apply hand torque only; avoid using pliers which may crack the connector housing.
4. Thermal Constraints: Verify that the routing path remains within the -51 deg C to +177 deg C range, avoiding direct contact with high-temperature steam lines or exhaust manifolds.