Product Overview

The Bently Nevada 330906-02-12-50-02-00 is a 3300 NSv reverse mount proximity probe. This probe has increased chemical resistance compared to the 3300 RAM probe. For process compressor applications, this enhanced resistance proves essential. The side-view characteristics of the 3300 NSv probe are also superior to those of the 3000-series 190 probe when gapping at the same distance from the target. The 330906-02-12 ordering code specifies 3/8-24 UNF threads for this reverse mount configuration. Total length reaches 5.0 meters (16.4 feet) as indicated by option 50. Connector option 02 provides a miniature coaxial ClickLoc connector with standard cable. Agency approval option 00 indicates no certifications are required for this model. The 330906-02-12-50-02-00 uses gold-plated brass ClickLoc connectors throughout the transducer system. ClickLoc connectors lock into place and prevent the connection from loosening under vibration. The patented TipLoc molding method provides a robust bond between the probe tip and the probe body.

Technical Specifications

General Specifications

Electrical Specifications

Measurement Specifications

Mechanical Specifications

Temperature & Environmental Specifications

Reverse Mount Configuration with 3/8-24 Threads

The 330906-02-12-50-02-00 uses a reverse mount design with 3/8-24 UNF threads. This imperial thread size suits North American mounting standards perfectly. The reverse mount probe installs from the opposite side of the machine casing compared to standard probes. For applications with limited access to the measurement point, this design proves invaluable. The probe case torque rating for reverse mount probes reaches 22.6 N•m (200 in•lb) maximum. For reliable operation without damage, Bently Nevada recommends 7.5 N•m (66 in•lb) of torque. Consequently, the 330906-02-12-50-02-00 installs securely without risk of thread stripping or case damage.

ClickLoc Connector System

The 330906-02-12-50-02-00 uses a miniature coaxial ClickLoc connector with standard cable. Option 02 specifies this connector type for reliable signal transmission. Gold-plated brass construction ensures excellent conductivity and corrosion resistance throughout. ClickLoc connectors lock into place with a positive engagement mechanism that technicians appreciate. Vibration cannot loosen a properly mated ClickLoc connection under normal operating conditions. For industrial machinery monitoring, this reliability proves absolutely essential for consistent measurements. The connector also provides environmental protection when mated to the corresponding extension cable.

Chemical Resistance & Side-View Characteristics

The NSv probe offers increased chemical resistance compared to the 3300 RAM probe. For process compressor applications, this enhanced resistance allows use in aggressive environments safely. Many process compressors contain chemicals that would damage standard probes over time. The side-view characteristics of the 3300 NSv probe are also superior to those of the 3000-series 190 probe. When gapping the 330906-02-12-50-02-00 at the same distance from the probe target, side-view performance improves noticeably. Therefore, this probe provides more consistent measurements in tight mounting spaces where access is limited.

Measurement Characteristics

Linear range for the 330906-02-12-50-02-00 reaches 1.5 mm (60 mils) for standard operation. This linear range begins at approximately 0.25 mm (10 mils) from the target surface. The range extends from 0.25 to 1.75 mm (10 to 70 mils) for full linear measurement. Output voltage spans approximately -1 to -13 Vdc across this complete linear range. The recommended gap setting measures 1.0 mm (40 mils) for optimal system performance. For system calibration, always pair this probe with a matching NSv Proximitor Sensor. The 330906-02-12-50-02-00 delivers accurate, repeatable measurements within these specifications consistently.

DC Resistance Characteristics

Probe DC resistance for the 330906-02-12-50-02-00 measures 5.3 ± 0.7 ohms at 5.0 meters length. This resistance represents the path from the center conductor to the outer conductor. For troubleshooting purposes, measure this resistance to verify cable integrity. A significant deviation from this specification may indicate cable damage. The relatively low resistance ensures minimal signal loss over the 5.0 meter length. For longer runs, the Proximitor Sensor compensates for additional cable resistance automatically.

Temperature Limitations

Operating temperature spans -52°C to +177°C (-62°F to +351°F) for the 330906-02-12-50-02-00. Storage temperature matches this same wide range for maximum flexibility. However, a critical low-temperature note applies to this probe model. Exposing the probe to temperatures below -34°C (-30°F) for a sustained period may cause premature failure of the pressure seal. Therefore, avoid prolonged operation below -34°C whenever possible for reliable service. The probe sealing material consists of a Viton O-ring designed for differential pressure sealing between the probe tip and case. For cold environment applications, consider additional thermal protection or consult Bently Nevada for specific guidance.

Field Wiring Guidelines

Field wiring connects the 330906-02-12-50-02-00 system to monitoring equipment at a distance. Wire gauge should measure 0.2 to 1.5 mm² (16 to 24 AWG) for standard connections. With ferrules, use 0.25 to 0.75 mm² (18 to 23 AWG) instead for secure termination. Bently Nevada recommends using three-conductor shielded triad cable for optimal noise rejection. Maximum length between the 3300 XL NSv Proximitor Sensor and the monitor reaches 305 meters (1,000 feet). Signal rolloff occurs at high frequencies when using longer field wiring lengths beyond this recommendation. Consult the frequency response graphs (Figure 16 and Figure 17) for specific rolloff characteristics at various frequencies. The 330906-02-12-50-02-00 maintains signal integrity within these published guidelines.

Installation Guidelines

Follow these steps for proper installation of the 330906-02-12-50-02-00.

1. Prepare the 3/8-24 UNF threaded hole in the machine casing.

2. Clean the threads thoroughly to remove any debris, oil, or old sealant.

3. Apply anti-seize compound to the probe threads for corrosion protection.

4. Thread the probe into the hole by hand until finger-tight initially.

5. Tighten to 7.5 N•m (66 in•lb) recommended torque. Do not exceed 22.6 N•m.

6. Connect the miniature coaxial ClickLoc connector to the extension cable.

7. Set the probe gap to 1.0 mm (40 mils) recommended starting point.

8. Verify the Viton O-ring seals properly by checking for any leaks.

Note: The 330906-02-12-50-02-00 requires protection from sustained temperatures below -34°C (-30°F). Do not exceed 22.6 N•m mounting torque under any circumstances. The 00 approval option indicates no hazardous area certifications for this model.

Packaging List

• One Bently Nevada 330906-02-12-50-02-00 NSv Reverse Mount Probe

• One miniature coaxial ClickLoc connector (attached to cable)

• One product calibration certificate

• One anti-static protective bag

Common FAQs

1. What is the length of the 330906-02-12-50-02-00?

This probe measures 5.0 meters (16.4 feet) in total length. The 50 option code specifies this particular length for extended reach. Other lengths are available with different option codes. For example, 10 indicates 1.0 meter for shorter runs. Choose the length that matches your probe-to-Proximitor distance. The 330906-02-12-50-02-00 with 50 suits installations where the Proximitor mounts far from the probe.

2. What threads does the 330906-02-12-50-02-00 use?

This reverse mount probe uses 3/8-24 UNF imperial threads. The 330906-02-12 ordering code specifies this thread type specifically. Maximum thread engagement should follow standard practices for 3/8-24 fittings. For metric thread requirements such as M10x1, order a different probe option instead. The 330906-02-12-50-02-00 suits North American imperial mounting systems exclusively.

3. What is the linear range of the 330906-02-12-50-02-00?

Linear range measures 1.5 mm (60 mils) for standard operation. This range begins at approximately 0.25 mm (10 mils) from the target surface. Linear range extends from 0.25 to 1.75 mm (10 to 70 mils) completely. Output voltage spans approximately -1 to -13 Vdc across this full range. The recommended gap setting is 1.0 mm (40 mils) for optimal system performance.

4. What is the low temperature limitation for the 330906-02-12-50-02-00?

Operating temperature spans -52°C to +177°C nominally for this probe. However, exposing the probe to temperatures below -34°C (-30°F) for a sustained period may cause premature pressure seal failure. The Viton O-ring seal becomes brittle at very low temperatures over time. For sustained cold operation below -34°C, consult Bently Nevada for application guidance. The 330906-02-12-50-02-00 requires careful temperature management in extreme cold environments.

5. What approvals does the 330906-02-12-50-02-00 carry?

The 00 agency approval option indicates no certifications are required for this model. This probe lacks CSA, ATEX, and IECEx approvals completely. For non-hazardous area installations only, the 330906-02-12-50-02-00 works perfectly. Hazardous area applications require a different approval option code such as 05 or CN. Verify your area classification before ordering this probe for any installation.

Why Choose This Probe?

The Bently Nevada 330906-02-12-50-02-00 delivers reliable NSv reverse mount measurement for non-hazardous process compressor applications. Increased chemical resistance allows use in aggressive environments where RAM probes would fail prematurely. Superior side-view characteristics improve gapping accuracy at standard distances significantly. 3/8-24 UNF imperial threads suit North American mounting requirements perfectly. ClickLoc connectors lock securely against vibration loosening without special tools. The Viton O-ring provides differential pressure sealing between tip and case reliably. For reverse mount applications requiring 5.0 meter length and no hazardous area approvals, choose the 330906-02-12-50-02-00.