330191-00-33-05-05 Bently Nevada 3300 XL 8 mm ETR Probe

Problem: Harsh Machine Environments Degrade Standard Probes

Rotating machinery in oil, gas, and power generation exposes proximity probes to vibration, chemical attack, and mechanical abuse. Standard probes often fail at the tip-to-body bond or cable junction, causing false trips and unplanned downtime. The Bently Nevada 330191-00-33-05-05 addresses these failure modes with patented TipLoc and CableLoc construction. This 3300 XL 8 mm ETR probe delivers engineering-grade precision for critical radial and axial displacement measurements.

Solution: 330191-00-33-05-05 Construction and Key Specs

The 330191-00-33-05-05 is a 3300 XL 8 mm ETR probe with a 3/8-24 UNF thread and no armor. Its 0.5 metre total length suits short-run installations where an extension cable is unnecessary. The probe tip uses polyphenylene sulfide (PPS) encapsulation, while the case is AISI 303 or 304 stainless steel. A Viton O-ring seals differential pressure between tip and case. The patented CableLoc design provides 330 N (75 lbf) pull strength at the probe case to lead junction.

• Input voltage: -17.5 Vdc to -26 Vdc (nonincendive, 12 mA max)
• Output resistance: 50 Ω
• Nominal probe DC resistance: 7.45 ± 0.50 Ω at 0.5 m
• Isolation: Differential pressure seal via Viton O-ring
• Thread: 3/8-24 UNF, max engagement 0.563 in
• Total length: 0.5 metre (1.6 feet)
• Case length: 3.3 in
• Unthreaded length: 0.0 in minimum
• Connector material: Gold-plated brass or beryllium copper
• Max connector torque: 0.565 N·m (5 in·lbf)

Problem: Electrical Noise and Ground Loops Corrupt Signals

Proximity probe systems are sensitive to supply variations and ground loops. The 330191-00-33-05-05 mitigates these issues with a supply sensitivity of less than 2 mV output change per volt input change. Its 50 Ω output resistance supports stable signal transmission. When installed with nonincendive circuits per drawing 140979, the probe operates from -17.5 Vdc to -26 Vdc at 12 mA maximum. With barriers, use -23 Vdc to -26 Vdc. Operation above -23.5 Vdc may reduce linear range.

Solution: Integration with 3300 XL Systems

The 330191-00-33-05-05 integrates with Bently Nevada extension cables and Prox transducers. One-metre systems do not use an extension cable, but this 0.5 m probe is designed for direct connection. The 75 Ω triaxial cable uses FEP insulation for standard temperature or PFA for extended range. Gold-plated connectors ensure low contact resistance. Maximum connector torque is 0.565 N·m (5 in·lbf). For fieldbus networks, wiring may require an external gateway or connection module; confirm cables and gateways with AutoDCSTech.

Problem: Extreme Temperatures and Chemical Exposure

The 330191-00-33-05-05 operates across a wide temperature range. For EPL Ga and Gc classifications, ambient temperature ranges from -55°C to +232°C depending on T-class. For EPL Dc, surface temperature limits apply from T90°C to T280°C. The PPS tip and stainless steel case resist oil, solvents, and corrosive fluids. The optional FluidLoc cable prevents liquid leakage through the cable interior. This probe carries multiple approvals for hazardous areas.