Description
Engineered for heavy-duty industrial turbomachinery displacement and vibration measurements, the Bently Nevada 330876-03-90-00-00 acts as a highly specialized transducer head within the 3300 XL 50 mm proximity transducer system. Incorporating a Polyphenylene Sulfide (PPS) tip and an AISI 304 stainless steel case, this sensor is designed to withstand severe process environments. The model features a smooth 1.99-inch diameter case with a side exit cable routing configuration, providing a profile optimized for tight physical envelopes. It comes equipped with a 9.0-meter (29.5 feet) integrated High Temperature FluidLoc Cable without armor, ensuring reliable signal propagation back to the companion proximitor sensor in high-temperature zones.
Features
- Large 50 mm tip diameter optimized for extended linear range measurements on large-scale steam/gas turbines and generators.
- Chemically resistant Polyphenylene Sulfide (PPS) probe tip material.
- Rugged AISI 304 stainless steel case construction for long-term mechanical stability.
- Viton O-ring seal design to prevent process medium bypass.
- High Temperature FluidLoc Cable design to resist fluid ingress and high thermal stress.
Applications
- Thrust position and shaft vibration monitoring in large utility steam turbines.
- High-power gas turbines and industrial generators.
- Heavy-duty process compressors and expanders.
- Hydroelectric turbine generator guide bearings.
Technical Specifications
| Parameter |
Specification |
| Manufacturer |
Bently Nevada |
| Model Code |
330876-03-90-00-00 |
| Series |
3300 XL 50 mm |
| Probe Case Option |
Smooth 1.99 in diameter - Side Exit (-03) |
| Total Length Option |
9.0 meters (29.5 feet) (-90) |
| Armor Option |
High Temperature FluidLoc Cable (-00) |
| Agency Approval Option |
No Approvals (-00) |
| Probe Tip Material |
Polyphenylene Sulfide (PPS) |
| Probe Case Material |
AISI 304 Stainless Steel (SST) |
| Sealing System |
Viton O-rings |
| Country of Origin |
United States |
| Shipping Weight (Calculated) |
5.0 kg |
Empirical Engineering Insights
Alternative Models & Compatibility
This 50 mm probe must be used with a matching 3300 XL 50 mm Proximitor Sensor configured for a 9.0-meter system length. Attempting to run this probe with standard 8 mm, 11 mm, or 25 mm Proximitor electronics will result in non-linear outputs, complete calibration errors, and compromised machinery protection.
Application Pitfalls & Engineering Notes
Because of the large 50 mm tip diameter, the radiated magnetic field is significantly wider than standard probes. Strict adherence to lateral clearance requirements from adjacent metal objects and neighboring probes is necessary to prevent cross-talk and side-wall interference. Ensure that the mounting bracket does not encroach on the active field zone of the probe tip.
Commissioning & Wiring Tips
The FluidLoc cable must never be spliced, cut, or altered. The precise electrical length of the 9.0-meter cable is part of the tuned radio frequency (RF) circuit; changing the length permanently alters the calibration curves. Always verify the DC gap voltage at the Proximitor output during mechanical installation to confirm you are within the linear operating range before locking the mounting assembly.
Installation Guidelines
CRITICAL WARNING: Verify that the machinery is completely shut down, locked out, and tagged out prior to installation. Ensure zero shaft rotation during the physical gapping procedure to prevent any physical contact between the probe face and the target surface, which will cause irreparable damage to the PPS tip.
1
Clean the mounting port and inspect the face to ensure it is free of metallic debris, burrs, or oxidation.
2
Insert the smooth probe case into the sleeve, ensuring the side exit cable direction is oriented to prevent sharp kinks.
3
Connect the probe to the extension cable and Proximitor sensor, powering the system to monitor DC voltage output.
4
Adjust the probe's physical gap until the target DC voltage (typically -10 Vdc for midpoint bias) is obtained, then torque the mounting clamps to secure the assembly.