Description

Option 22 (2.2 inches unthreaded length) and Option 40 (4.0 inches overall case length) specify this unarmored 1/4-28 UNF-threaded 3300 NSv proximity probe configuration — 330901-22-40-10-01-00. This configuration features a 1.0 meter total probe length (Option 10), a miniature coaxial ClickLoc connector supplied with a pre-installed connector protector (Option 01), and does not require hazardous area approvals (Option 00). It is used in applications with reduced target area geometry and tight clearances, working in conjunction with a 3300 XL NSv Proximitor Sensor and extension cable to measure shaft vibration and axial position.

In contrast to armored variants (such as the 330902 series) or models with larger threads (like the 3/8-24 UNF 330908 series), this unarmored 1/4-28 UNF model provides a narrow physical envelope for installations with limited radial clearance. The integrated ClickLoc connector protector guards against moisture, turbine oil, and other process contaminants, preserving signal integrity at the critical probe-to-extension cable junction. The probe tip is made from polyphenylene sulfide (PPS) and is joined to the AISI 304 stainless steel case using TipLoc molding, providing a seal against differential pressure.

Features

• Option 22 unthreaded length of 2.2 inches allows deep recess mounting.
• Option 40 overall case length of 4.0 inches matches standard narrow-clearance machine casings.
• Option 10 total probe length of 1.0 meter offers a direct connection to adjacent junction boxes.
• Option 01 ClickLoc coaxial connector includes an integrated fluorosilicone connector protector to block liquids.
• Unarmored design offers greater cable flexibility with a minimum bend radius of 25.4 mm (1.0 in).
• 1/4-28 UNF-2A thread diameter fits small-bore tapped mounting locations.
• TipLoc molding process joins the polyphenylene sulfide tip to the stainless steel case for pressure sealing.
• CableLoc design establishes a 220 N (50 lb) pull strength between the coaxial cable and the probe tip.

Applications

• Small-bore rotating machinery including pumps, centrifugal compressors, and high-speed expanders.
• Aeroderivative gas turbines with limited physical target geometry.
• Centrifugal compressors where fluid sealing and chemical resistance are required.
• Standard industrial machinery needing non-contact radial vibration and axial position measurements under tight clearances.

Ordering Information

Technical Specifications

Installation Guidelines

• When drilling and tapping a mounting hole for a 1/4-28 UNF probe, a #3 or larger tap drill is recommended.
• Ensure that the maximum thread engagement length does not exceed 0.375 inches for 1/4-28 UNF probe cases to avoid binding.
• Apply a probe case installation torque of 5.1 N m (45 in lb) recommended, up to a maximum rated torque of 7.3 N m (65 in lb).
• Torque connector-to-connector joints finger tight, ensuring maximum torque does not exceed 0.56 N m (5 in lb).
• Verify probe gap adjustment using a multimeter on the Proximitor Sensor output, targeting approximately -7.0 Vdc to -8.0 Vdc (1.0 mm / 40 mils gap) for standard center-range calibration.
• Maintain a minimum shaft target diameter of 31 mm (1.2 in) to avoid measurement errors. Target diameters under 20 mm (0.8 in) require custom system calibration.

Compliance and Certifications

• No hazardous area agency approvals are required for this specific option configuration (Option 00).