Description
Optimized for machinery protection systems, the Bently Nevada 330171-20-55-05-02-CN delivers non-contact, high-precision radial vibration and axial position feedback in critical rotating machinery. Featuring a high-temperature polyphenylene sulfide (PPS) tip and a rugged AISI 303/304 stainless steel threaded body, this 3300 5 mm proximity probe is built to maintain signal integrity in volatile industrial environments. The integrated ClickLoc miniature coaxial connector establishes a secure, low-impedance connection with standard triaxial 75 ohm FEP-insulated cables, ensuring minimal loss over the 0.5-meter system length.
Features
-
Premium Materials: Constructed with a high-durability polyphenylene sulfide (PPS) tip and AISI 303/304 stainless steel housing for superior corrosion and wear resistance.
-
Engineered Threading: Threaded 1/4-28 UNF physical casing without armor, configured for straightforward integration.
-
Rugged Cabling: Fitted with a 75 ohm triaxial, fluoroethylene propylene (FEP) insulated probe cable designed to withstand industrial chemical exposure.
-
ClickLoc Interconnect: Miniature coaxial ClickLoc connector provides a positive, vibration-resistant physical lock under continuous operating conditions.
-
Wide Thermal Range: Maintains electrical calibration and physical stability across temperatures ranging from -35 degC to +177 degC.
Applications
- Radial vibration and shaft position monitoring in heavy industrial steam and gas turbines.
- Thrust position and axial displacement tracking in high-speed compressors and turbocompressors.
- Industrial machinery protection systems integrated within Bently Nevada 3500 series monitoring racks.
- Sub-millimeter shaft movement and eccentricity measurement in power generation and petrochemical facilities.
Technical Specifications
| Parameter |
Specification Value |
| Manufacturer |
Bently Nevada |
| Model Number |
330171-20-55-05-02-CN |
| Probe Diameter |
5 mm |
| Thread Profile |
1/4-28 UNF (without armor) |
| Unthreaded Length |
2.0 inches (Option 20) |
| Overall Case Length |
5.5 inches (Option 55) |
| Total Cable Length |
0.5 meter / 1.6 feet (Option 05) |
| Connector Option |
Miniature coaxial ClickLoc connector, standard cable (Option 02) |
| Agency Approvals |
CN (Country-specific hazardous location approvals) |
| Probe Tip Material |
Polyphenylene sulfide (PPS) |
| Case Material |
AISI 303 or 304 stainless steel |
| Probe Cable Type |
75 ohm triaxial, FEP-insulated |
| Tensile Strength |
222 N (50 lbf) probe case to probe lead; 222 N (50 lbf) lead to extension connector |
| Operating Temperature Range |
-35 degC to +177 degC (-31 degF to +351 degF) |
| Pressure Sealing |
Fluorocarbon O-ring differential pressure seal |
| Net Weight |
0.323 kg |
| Shipping Weight |
2.00 kg (as packaged) |
| Country of Origin |
United States (U.S.A.) |
Alternative Models & Compatibility
The Bently Nevada 3300 5 mm proximity probe is backward-compatible with 3300 XL 5 mm extension cables and Proximitor sensors. Ensure that the total electrical length of the probe and extension cable combined matches the calibrated length of your Proximitor sensor (typically 5.0 meters or 9.0 meters). Calibration settings require verification when swapping older 7200 series proximity probes due to differences in linear range and voltage scale factors (200 mV/mil).
Application Pitfalls & Engineering Notes
During mechanical installation, physical thermal expansion of the machine housing must be calculated. At high operating temperatures, turbine rotor growth can shift the nominal gap beyond the linear range of the sensor. The PPS tip is resilient against chemicals but susceptible to mechanical fracture; avoid direct impact during insertion through internal brackets. Ensure the fluorocarbon O-ring seal is seated properly inside the probe case to prevent pressure differential leakage.
Commissioning & Wiring Tips
Keep the coaxial connector interfaces completely clean and free of moisture or lubricating grease. Any oil residue on the ClickLoc interface introduces high-frequency contact resistance, leading to false high-vibration readings or signal anomalies on the 3500 rack monitor. Secure the extension cable using non-conductive, self-locking clamps to prevent vibration-induced cable fatigue, ensuring the bend radius does not fall below 25.4 mm (1 inch).
Installation Guidelines
CRITICAL WARNING: De-energize and lock out all machinery before starting installation or mechanical adjustment. Verify that all residual system pressure is safely vented. Never exceed the rated case torque of 1/4-28 UNF threads to avoid catastrophic casing deformation.
1
Measure and verify the target unthreaded length and ensure the 5.5-inch case depth clears all internal physical casing blockages inside the housing.
2
Carefully thread the probe into the mounting bracket or housing using hand pressure to prevent cross-threading the fine 1/4-28 UNF threads.
3
Set the nominal sensor gap mechanically while monitoring the DC voltage output of the matching Proximitor sensor using a calibrated digital voltmeter (typically targeting -10.0 V DC for mid-range calibration).
4
Lock the probe body in place using a standard locknut, torqueing to a maximum of 4.5 N-m (40 in-lb) to prevent damage to the stainless steel body.