Product Overview

The Bently Nevada 330881-16-00-395-06-02 PROXPAC XL assembly represents a sophisticated integration of the industry-standard 3300 XL 8mm proximity probe and a Proximitor sensor into a single, robust housing. Engineered for critical rotating machinery, this transducer provides high-precision vibration and position measurements in environments where external mounting of separate sensors is impractical. It effectively monitors shaft vibration, eccentricity, and thrust position in steam turbines, gas turbines, and large industrial compressors. By consolidating the signal conditioning electronics within the mounting assembly, the PROXPAC XL eliminates complex cabling requirements and enhances signal integrity, ensuring your Machinery Protection System (MPS) receives instantaneous, accurate data for emergency shutdown and diagnostic analysis.

Model Suffix & Hardware Decoding

330881 Suffix Logic Breakdown

Each digit in the 330881 configuration defines the mechanical and electrical characteristics essential for field compatibility:

Probe and Fitting Option (-16)

The 16 suffix specifies a 3300 XL 8mm probe with a 3/8-24 UNF thread, featuring a reverse-mount probe configuration tailored for integrated housings.

Standoff Adapter Option (-00)

The 00 designation indicates no standoff adapter is required, allowing for a direct and low-profile installation against the machine casing or bearing housing.

Probe Penetration (-395)

The 395 suffix translates to a 3.95-inch probe penetration depth. This precise length ensures the probe tip maintains the optimal gap relative to the target shaft surface for accurate linear measurement.

Mounting Thread (-06)

The 06 code defines the mounting thread as 3/4-14 NPT, providing a standardized, leak-proof mechanical interface for industrial conduit and housing entry points.

Agency Approval (-02)

The 02 approval option provides multi-national hazardous area certifications, including ATEX and CSA, allowing deployment in Zone 0, 1, and 2 environments.

Core Technical Parameters

Field Installation Guidelines

Engineers must ensure the target shaft material matches the AISI 4140 steel calibration standard to maintain the specified 200 mV/mil scale factor. During installation, set the mechanical gap to approximately 1.27 mm (50 mils) to achieve a quiescent gap voltage of roughly -10 VDC. This places the sensor in the center of its linear range. Utilize the internal terminal block for signal wiring, ensuring that the shield remains isolated from the PROXPAC housing to prevent ground loops. Verify that the probe penetration depth (3.95 inches) does not result in mechanical contact with the shaft during thermal expansion cycles.

Mechanical & System Advantages

The PROXPAC XL housing acts as a primary shield against environmental contaminants, including oil mist, moisture, and mechanical impact. Its integrated design significantly reduces the footprint required for instrumentation, making it the preferred choice for retrofitting older turbines with modern 3500-series monitoring racks. This assembly seamlessly interfaces with Bently Nevada’s System 1 software platform, enabling predictive maintenance through high-resolution trend data. The use of the 3300 XL 8mm probe technology inside the assembly guarantees backward compatibility with existing cable lengths and monitoring modules while providing superior temperature stability.

Shipping & Global Fulfillment

We prioritize speed and security for all international shipments to minimize downtime.

Dispatch Schedule: 2-7 days when payment finish, depending on current stock levels and certification requirements.

Global Logistics: We ship via DHL, FEDEX, and UPS to ensure tracked, door-to-door delivery.

Heavy-Duty Packaging: Each unit is encased in anti-static industrial packaging and secured with high-density foam inserts. Our specialized shipping boxes are rated for international transit to guarantee the sensor arrives in calibrated condition.

Essential Technical Q&A

Q1: What happens if my shaft is not AISI 4140 steel?

A1: The transducer will still function, but the scale factor will change. You must perform a field calibration using a spindle micrometer to determine the actual mV/mil sensitivity for your specific metallurgy.

Q2: Can the internal Proximitor be replaced without removing the entire housing?

A2: Yes, the design allows for internal access to the signal conditioning electronics, though the probe remains fixed unless the entire assembly is unbolted for depth verification.

Q3: Does this 330881 model support 5-meter or 9-meter system lengths?

A3: The suffix 330881-16 is typically configured for a 9-meter system length. Always verify the label on the internal Proximitor module to ensure it matches your extension cable and probe total electrical length.