The Bently Nevada 21747-040-00, also cataloged as the 21747-040-00 Extension Cable, operates as a dedicated hardware component for signal transmission between proximity probes and Proximitor sensors within 3300 Monitoring Systems.

Cable Configuration Matrix

The 21747 series extension cable utilizes a standard coaxial interface to maintain signal continuity. The "-040" designator indicates a specific length of 4.0 meters, while the "-00" suffix denotes standard construction without armor. This configuration ensures impedance matching between the transducer and the signal processing module.

Physical and Electrical Specifications

Rotor Dynamics and Signal Integrity

The use of the 21747 extension cable is essential for maintaining the integrity of rotor dynamics measurements. Accurate eddy-current probe scaling relies on the total system length (Probe + Extension Cable) being exactly as specified by the calibration curve. Deviations from the calibrated length will introduce phase shifts and magnitude errors. Cross-talk suppression is maintained via the double-shielded construction of the cable, ensuring that high-frequency vibration signals remain isolated from electromagnetic interference present in industrial environments.

Ordering Inclusions

• 21747-040-00 Extension Cable (4.0 m)

• Connector protective caps

• Standard instruction documentation

Field Installation Procedures

• Clean all connector surfaces with an approved solvent before mating to prevent signal attenuation.

• Tighten coaxial connectors by hand until firm; do not use pliers to prevent connector housing deformation.

• Secure the cable along the mechanical housing using insulated clamps, maintaining a minimum bend radius of 50 mm.

• Ensure the cable routing does not cross over high-power conduits to avoid induced noise on the sensor loop.

• Verify continuity between the sensor and the monitor end after installation to ensure no shield breaks occurred during pulling.

Logistics Logistics

• Delivery time: 2-7 days when payment finish.

• Dispatched via DHL/FEDEX/UPS.

• Units are secured within anti-static industrial packaging to prevent damage to sensitive coaxial pins and dielectric materials.

Frequently Asked Questions

• Can this cable be used with non-Bently probes? Performance specifications are only guaranteed when used with compatible 3300 series proximity transducer systems.

• Is the connector waterproof? The connectors are designed to be weather-resistant when properly mated, but they are not rated for full submersion.

• What is the impact of a cable kink? Kinking degrades the dielectric, changing the characteristic impedance and causing signal distortion.

• Can I splice this cable? Splicing is strictly prohibited, as it introduces impedance discontinuities and reflections.

• Why is the center conductor often damaged? Over-tightening or twisting the connector during mating frequently shears the center pin.

• Is the shield grounded? The shield should only be grounded at the monitor end to avoid ground loop current.

• Does length affect gap voltage? Total system capacitance changes with length, which directly impacts the -10 VDC gap voltage target calibration.

• Can I leave the unused end exposed? Connectors must be capped to prevent oxidation and moisture ingress.