Product Overview

The Bently Nevada 330707-00-25-10-12-00 is a high-precision 3300 XL 11 mm eddy current proximity probe designed for critical machinery protection systems. This transducer is utilized for non-contact measurement of axial displacement (thrust), differential expansion, and vibration in large rotating machinery. The 11 mm system provides an extended linear range of 4.0 mm (160 mil) with a standard sensitivity of 3.94 V/mm (100 mV/mil).

This specific configuration features a 5/8-18 UNF threaded body with a 2.5-inch overall case length and no unthreaded section. The probe is equipped with a 1.0-meter FluidLoc cable—engineered to prevent fluid migration through the cable interior—and a miniature coaxial ClickLoc connector. As indicated by the -00 suffix, this unit is intended for applications where specific agency approvals for hazardous areas are not required.

Technical Configuration

Ordering Information

Industrial procurement and replacement tasks must reference the complete option breakdown to ensure exact mechanical and electrical compatibility.

• Part Number: 330707-00-25-10-12-00

• Replacement Advice: Because 11 mm probes are critical for thrust and differential expansion protection, verify if the corresponding Proximitor sensor requires simultaneous replacement.

• System Integrity: Always ensure all system components (Probe, Extension Cable, and Proximitor) are 3300 XL 11 mm series, typically identified by purple color coding.

Engineering & Installation Guide

Installation Steps (Gap Adjustment)

To ensure accurate measurement within the 4.0 mm linear range, the probe must be gapped correctly during installation:

• Mechanical Pre-installation: Thread the probe into the mounting bracket or bearing cap. Rotate the probe body only before connecting the cable to avoid twisting the integrated 1.0-meter lead.

• Electrical Monitoring: Connect the probe to the appropriate 3300 XL 11 mm Proximitor and apply -24 Vdc power. Monitor the DC voltage between the OUT and COM terminals.

• Gapping: Gradually thread the probe toward the target surface. Adjust until the DC voltage reaches approximately -10.0 Vdc, which represents the center of the linear range (a gap of roughly 2.3 mm / 90 mil).

• Final Torque: Tighten the locknut to the recommended torque of 15.2 N·m (133 in·lb); do not exceed 45.2 N·m. Verify the voltage after tightening to ensure the probe did not shift.

Field Wiring Guide

• Probe to Extension Cable: Hand-tighten the ClickLoc connectors (maximum torque 0.565 N·m). The use of connector protectors is highly recommended to prevent fluid or moisture ingress.

• Proximitor to Monitor: Use 3-wire shielded cable (16 to 24 AWG) to connect the Proximitor to monitoring modules like the 3500/42M.

• VTX (-24V): Connect to the monitor’s -24Vdc power output.

• COM (GND): Connect to the signal common.

• OUT (SIG): Connect to the signal input (delivers -1V to -17V range).

• SHLD: Ground the shield at the monitor end only to prevent ground loops.

FAQ

• What is the benefit of the FluidLoc cable (Option 12)?

  It prevents oil and other machine fluids from leaking through the cable into junction boxes or monitors, which is critical for pressurized housing applications.

• Can I mix 11 mm components with 8 mm components?

  No. Components must be matched by series. Mixing 11 mm probes with 8 mm Proximitors will result in significant measurement errors.

• What target material is required?

  Standard calibration is for AISI 4140 steel; use with other materials will require scale factor adjustments.