Product Introduction
The Bently Nevada 330171-00-20-90-02-05 is a precision 5mm proximity probe designed for industrial automation applications. Part of the 3300 series, this probe uses a 1/4-28 UNF thread and Polyphenylene sulfide (PPS) tip to provide accurate, non-contact displacement measurements. Its robust construction and multiple approvals make it a trusted choice for vibration monitoring in rotating equipment.
Common failure modes in proximity probes include drifts due to temperature changes, cable damage, and improper mounting torque. The 330171-00-20-90-02-05 addresses these with a wide temperature range from -35°C to +177°C, a rugged 75 Ω triaxial FEP cable, and precise torque specifications to ensure secure installation without over-tightening.
Technical Specifications
Below are key specifications from the manufacturer for the Bently Nevada 330171-00-20-90-02-05. These values are critical for proper system integration and troubleshooting.
| Parameter |
Value |
| Probe Tip Material |
Polyphenylene sulfide (PPS) |
| Probe Case Material |
AISI 304 stainless steel |
| Probe Case Thread |
1/4-28 UNF |
| Maximum Thread Engagement |
0.375 in |
| Total Length |
9.0 metres (29.5 feet) |
| Connector Option |
Miniature coaxial ClickLoc connector, standard cable |
| Weight |
0.323 Kg |
| Power Requirement |
-17.5 Vdc to -26 Vdc at 12 mA max |
| Output Resistance |
50 W |
| Probe DC Resistance (9m) |
9.87 Ω ± 0.90 |
| Probe Temperature Range |
-35°C to +177°C |
| Probe Case Torque (recommended/max) |
5.1 N·m / 7.3 N·m |
| Minimum Cable Bend Radius |
25.4 mm (1.0 in) |
Application & Use Cases
The Bently Nevada 330171-00-20-90-02-05 excels in vibration monitoring for turbines, compressors, and pumps. Its 5mm sensing range and high linearity (less than 2 mV change per volt supply variation) ensure accurate readings even in noisy environments. For example, in a steam turbine train, this probe detects shaft vibration at gaps from 10 to 90 mil, with documented magnetic field immunity up to 300 Gauss at 60 Hz.
Common failure modes addressed: The probe's PPS tip resists chemical attack, while the stainless steel case prevents corrosion. The 0.375 in thread engagement limit prevents stripping of mounting threads, a frequent cause of premature failure.
Installation & Setup Guidance
Proper installation is vital to avoid failure. For the Bently Nevada 330171-00-20-90-02-05, drill a #3 or larger tap drill for the 1/4-28 thread. Use a recommended torque of 5.1 N·m (45 in·lb) and never exceed 7.3 N·m (65 in·lb). The connector-to-connector torque should be a maximum of 0.565 N·m (0.42 ft·lbf). Ensure the cable bend radius does not fall below 25.4 mm (1.0 in) to avoid internal damage.
Set the initial gap at 1.27 mm (50 mils) for optimal linear range, and verify power supply between -17.5 Vdc and -26 Vdc. Operation above -23.5 Vdc may reduce linear range—a common mistake that leads to erroneous readings.
Maintenance & Reliability
Regularly inspect the cable for cuts or kinks, especially near the connector. The probe operates reliably in ambient temperatures from -35°C to +177°C, but exposure below -34°C may cause premature pressure seal failure. For hazardous locations, refer to the temperature classification schedules (e.g., T1 to T5) to ensure compatibility with gas groups. Routine cleaning of the probe tip with a soft cloth is sufficient; avoid solvents that could damage the PPS material.
By adhering to torque limits and avoiding over-tightening, you maximize the service life of the Bently Nevada 330171-00-20-90-02-05. These practices directly reduce downtime and replacement costs.
Buying Guide
Before purchasing, confirm your system requires a 5mm probe with 1/4-28 thread and a 9-meter cable. The 330171-00-20-90-02-05 includes a miniature coaxial ClickLoc connector and has multiple agency approvals (option 05). For assured authenticity and support, source this part from PLC Source PRO, a trusted distributor of industrial automation spares.