330130-085-00-00 | Bently Nevada | 3300 XL Standard Extension Cable

The Bently Nevada 330130-085-00-00, also cataloged as the 330130 Standard Extension Cable, operates as a dedicated hardware component for signal transmission between 3300 XL Proximitor sensors and eddy-current transducers within machine monitoring systems. This assembly maintains the electrical impedance required to preserve the linear relationship between probe gap and output voltage.

Hardware Specifications

Eddy-Current Probe Scaling and Gap Voltage Validation

The accuracy of the 3300 XL proximity transducer system depends on the total electrical length of the probe, extension cable, and Proximitor sensor assembly. The 330130 extension cable is calibrated to ensure the system maintains a nominal scale factor of 7.87 V/mm (200 mV/mil). During installation, the gap voltage must be validated at the Proximitor terminal block; a target of -10 VDC is standard for the linear center of the operating range. Deviations from this voltage during cold-start or operational monitoring conditions indicate potential probe damage, cabling shield interference, or improper target material contact. Proper cross-talk suppression must be maintained by ensuring cables are routed away from high-frequency switching noise sources.

Frequently Asked Questions

Q: Can the 330130 extension cable be used with non-standard target materials?

A: Yes, but the system must be recalibrated. Factory calibration is optimized for AISI 4140 steel. If the target material varies in magnetic permeability or electrical resistivity, the linear scale factor will shift, necessitating a site-specific calibration curve.

Q: Is it acceptable to use this cable for Overspeed protection systems?

A: Yes, provided the total system response time and frequency response are verified for the specific turbine or shaft rotational speed. Signal attenuation over the 8.5 m length must be factored into the overall safety loop latency calculation.

Field Installation Guidelines

• Shield Integrity: Maintain the continuity of the shield through the extension cable connectors. The shield must be grounded at the Proximitor end only to prevent ground loop currents from introducing signal noise.
• Cable Routing: Avoid routing the extension cable alongside AC power lines or high-current DC cables. Maintain a minimum separation distance as defined by local site standards to mitigate electromagnetic interference.
• Connector Care: Inspect connectors for oxidation or contamination prior to mating. The use of a contact cleaning agent is recommended. Ensure the connection is tightened to prevent mechanical vibration from causing intermittent signal drops.
• Bend Radius: Adhere to a minimum static bend radius of 25.4 mm (1.0 inch) to avoid damaging the internal coaxial geometry and shifting the cable characteristic impedance.