The Bently Nevada 330703-000-050-10-01-00, also cataloged as the 330703 Proximity Probe, operates as a dedicated hardware component for non-contacting vibration and displacement measurements within a Bently Nevada 3500 Machinery Protection System.

Suffix Breakdown & Model Matrix

• 330703: 3300 XL 11 mm Proximity Probe, M14 x 1.5 threaded case, without armor.

• 000: Unthreaded Length option (0 mm).

• 050: Overall Case Length option (50 mm).

• 10: Total Length option (1.0 meter, approximately 3.3 feet).

• 01: Connector and Cable Option (Miniature coaxial ClickLoc connector, standard cable).

• 00: Agency Approval option (No standard hazardous area certification flags specified).

Hardware Specifications

Eddy-Current Probe Scaling and Gap Voltage Validation

The 3300 XL 11 mm system utilizes radio frequency eddy-current principles to deliver an extended linear measurement range compared to standard 8 mm variants. Proper transducer loop operation depends directly upon accurate eddy-current probe scaling configured to the target shaft metallurgy. During loop commissioning, field verification requires strict gap voltage validation to ensure the probe is mechanically positioned inside its linear calibration envelope.

Adjusting the physical clearance until the output driver produces exactly -10 VDC targets the precise midpoint of the 4.0 mm linear curve. This proper baseline voltage is required to prevent loop saturation during high-amplitude rotor dynamics changes. Furthermore, mechanical installation configurations must enforce separation thresholds from adjacent structures to guarantee cross-talk suppression and isolate actual shaft displacement from parasitic inductive field interference.

Frequently Asked Questions

Q: Can this 330703 11 mm probe be connected directly to an 8 mm 3300 XL Proximitor Sensor?

A: No. The internal electronics of an 8 mm sensor are calibrated for a different eddy-current probe scaling profile and a 7.87 V/mm output. The 11 mm probe must be paired exclusively with a 3300 XL 11 mm Proximitor Sensor to achieve the correct 3.94 V/mm scale factor.

Q: What are the consequences of extending or shortening the 1.0-meter integral cable in the field?

A: Proximity probe cables cannot be altered, spliced, or repaired in the field. The electrical length of the probe and extension cable forms a balanced RF circuit. Any alteration modifies loop impedance, corrupts factory calibration scaling, and results in a permanent Transducer Fault (NOT OK) flag.

Q: Is hot-swapping the ClickLoc coaxial connector safe while the monitoring rack is online?

A: Separating the ClickLoc connector during machine operation will break the current loop, instantly causing a Transducer Fault status on the matching monitor card. To avoid triggering false trip signals on safety relays, the corresponding channel logic must be bypassed prior to disconnecting the coaxial circuit.

Field Installation Guidelines

• Mechanical Torque Limits: When threading the M14 x 1.5 case into its mounting bracket, do not exceed the maximum allowable installation torque limit of 27.0 N-m (240 in-lb) to prevent case distortion or failure of the tip joint.

• Physical Clearance Constraints: To maintain full cross-talk suppression and prevent side-viewing interference from surrounding structural steel, ensure a minimum counterbore diameter of 50.8 mm (2.0 in) is maintained around the probe tip when recessed into a housing.

• ClickLoc Connector Interface: Ensure all coaxial connections are clean and dry before mating. Lock the ClickLoc connector firmly by hand until a physical tactile click is verified. Do not use mechanical pliers or wrenches to tighten the connection, as over-tightening fractures the internal insulation layers.

• Cable Bend Radius Profile: Ensure the integrated coaxial cable does not drop below a minimum static bend radius of 25.4 mm (1.0 in). Avoid sharp kinks or compression stress from tight cable ties along the routing path.

• Ground Isolation Protocol: Keep the outer coaxial shield insulated from the machinery casing ground. The entire loop must utilize a single-point grounding layout, running unbroken from the probe tip and terminating exclusively at the designated ground terminal of the Proximitor Sensor station.