Product Overview
The Bently Nevada 330708-00-20-50-02-05 is a 3300 XL 11 mm Proximity Probe designed for precise shaft displacement and vibration measurements in rotating machinery. This model features a 5/8-18 UNF thread, unthreaded length of 0 inches, an overall case length of 2.0 inches, and a total length of 5.0 meters (16.4 feet). The probe uses a miniature coaxial ClickLoc connector with standard cable and holds multiple agency approvals. Its polyphenylene sulfide (PPS) tip and AISI 304 stainless steel case deliver durability in harsh environments.
Technical Specifications
Key parameters for the Bently Nevada 330708-00-20-50-02-05 include:
| Specification |
Value |
| Probe Length (m) |
5.0 |
| DC Resistance (RPROBE) |
7.2 ± 0.8 ohms |
| Case Thread |
5/8-18 |
| Max Thread Engagement |
0.938 in |
| Operating/Storage Temperature |
-52°C to +177°C |
| Probe Tip Material |
Polyphenylene sulfide (PPS) |
| Case Material |
AISI 304 SST |
| Cable Type |
75 Ω triaxial, FEP insulated |
| Connector Type |
Miniature coaxial ClickLoc |
| Agency Approvals |
Multiple Approvals |
Common Failure Modes and How This Model Addresses Them
Proximity probes often fail due to cable damage, seal leakage, or temperature extremes. The Bently Nevada 330708-00-20-50-02-05 mitigates these risks with a 75 Ω triaxial FEP-insulated cable resistant to chemicals and abrasion. The Viton O-ring pressure seal maintains integrity under differential pressure, though probes are not pressure-tested before shipment. Operating from -52°C to +177°C, this probe withstands the thermal demands of turbines and compressors. Its PPS tip resists wear and environmental attack, reducing false readings from tip degradation.
Industry Applications
Common uses for the Bently Nevada 330708-00-20-50-02-05 include vibration monitoring on steam turbines, centrifugal compressors, and large electric motors. In a typical installation on a 10 MW compressor, the probe's 5-meter cable length allows connection to a remote Proximitor sensor without signal degradation. The 5/8-18 thread simplifies mounting in standard probe holders, while the ClickLoc connector ensures reliable signal transmission under vibration.
Installation and Setup Guide
When installing the Bently Nevada 330708-00-20-50-02-05, ensure the thread engagement does not exceed 0.938 inches to avoid bottoming. Apply the recommended probe case torque of 15.2 N·m (133 in·lb); maximum is 45.2 N·m (400 in·lb). The connector-to-connector torque should be finger tight, with a maximum of 0.565 N·m (5 in·lb). Maintain a minimum bend radius of 25.4 mm (1.0 in) on the cable to prevent internal damage. For proper performance, pair this probe exclusively with a five-meter Proximitor sensor as designed.
Maintenance and Reliability
Routine inspection of the Bently Nevada 330708-00-20-50-02-05 should focus on cable condition, connector tightness, and seal integrity. The FEP cable insulation resists moisture and many oils, but frequent thermal cycling can cause embrittlement over time. Check the O-ring seal annually in high-temperature applications (above 125°C). Avoiding temperatures below -34°C prolongs pressure seal life. The probe’s stainless steel case withstands corrosion in wet or chemically aggressive environments.
Selection Guide and Purchasing Advice
Before ordering the Bently Nevada 330708-00-20-50-02-05, verify your system requires a 5-meter probe with the 5/8-18 thread and ClickLoc connector. This model is not compatible with shorter or longer cable configurations unless paired with the matching Proximitor. For custom pressure testing or special cable lengths, contact the manufacturer. As a trusted supplier, UBEST Automation (ubest101.myshopify.com) offers this genuine Bently Nevada probe with fast shipping and technical support.