Description

The Bently Nevada 330780-91-00 operates as a high-performance 3300 XL series proximity sensor specifically engineered for an 11 mm transducer system. It provides non-contacting shaft displacement, axial position, and vibration monitoring. The internal electronics continuously convert high-frequency radio frequency (RF) eddy-current gap modulations into a highly accurate, proportional analog DC voltage. This 11 mm system is primarily utilized when an extended linear range is mandatory—such as in axial thrust applications—offering a wider range than standard 5 mm or 8 mm systems. It transmits data directly to machinery protection platforms like the Bently Nevada 3500 series without requiring any on-site field calibration.

Hardware Specifications

Transducer Electronics and RFI Resilience

The Bently Nevada 330780-91-00 relies on advanced internal circuitry that inherently rejects radio frequency interference (RFI) and electromagnetic interference (EMI). Because the sensor blocks this noise, it operates reliably in electrically noisy environments, such as those affected by nearby variable frequency drives (VFDs). The internal oscillator conditions the dynamic signal over a 4.0 mm (160 mils) linear range, delivering a nominal scale factor of 100 mV/mil. The system provides complete backwards-compatibility, functioning as a direct technical upgrade to replace older legacy 7200-series 11 mm and 14 mm transducer hardware.

Frequently Asked Questions

Q: What specific hardware variables do the “-91” and “-00” option codes define?

A: The option code -91 designates a 9.0-meter total system length configured for standard DIN rail mounting. Because this unit integrates a 9.0-meter calibration curve directly, it must be paired with a corresponding 11 mm probe and cable system totaling exactly 9.0 meters. Meanwhile, the option code -00 indicates the standard commercial version intended for non-hazardous locations, meaning it carries no specialized explosion-proof or intrinsically safe agency approvals.

Q: What type of wiring terminals does this unit feature?

A: This Proximitor utilizes integrated SpringLoc terminal strips. These connectors provide a gas-tight, vibration-resistant connection that eliminates the risk of screw-type terminals loosening over time under heavy mechanical machinery vibration.

Field Installation Guidelines

• Shielding and Ground Isolation: First, connect the coaxial probe or extension cable securely using the integrated, gold-plated ClickLoc connectors. Turn them finger-tight until you hear an audible click. Next, connect the overall outer shield of the field wiring to the terminal block. Finally, maintain single-point instrumentation ground isolation exclusively at the monitor rack panel.
• Mounting Requirements: Because the “91” suffix provides integrated high-density DIN-rail clips, you can snap the unit directly onto a standard 35 mm DIN rail. The built-in mounting base eliminates the need for separate isolator plates by providing complete electrical isolation.
• Linear Gap Calibration: During field commissioning, mechanically gap the 11 mm proximity probe target surface until the static DC terminal output registers a true center-range voltage measurement of -9.0 VDC. This value establishes the ideal physical midpoint within the linear measurement window.