Product Overview

The Bently Nevada 330500-07-04 is a high-precision Velomitor Piezo-velocity sensor engineered to monitor absolute casing vibration on rotating machinery. By utilizing an internal piezoelectric ceramic element and an integrating circuit, this solid-state transducer converts acceleration into a velocity signal. This architecture provides a significant advantage over legacy moving-coil velocity sensors by eliminating internal moving parts that are prone to mechanical wear and fatigue. The result is a more durable and stable measurement device capable of detecting rotor unbalance, misalignment, and other mechanical malfunctions across a wide frequency range.

Technical Hardware Parameters

The 330500-07-04 configuration is built for reliability in harsh industrial environments, featuring a hermetically sealed 316L stainless steel housing and high-fidelity signal conditioning.

• Model Number 330500-07-04

• Transducer Type Piezo-velocity (Solid-state)

• Sensitivity 3.94 mV/mm/s (100 mV/in/s) ±5%

• Frequency Response 4.5 Hz to 5.0 kHz (270 to 300,000 cpm) ±3.0 dB

• Velocity Range Up to 1270 mm/s (50 in/s) peak

• Mounting Thread M10 x 1.25 (Option -07)

• Agency Approvals Multiple hazardous area certifications including ATEX and IECEx (Option -04)

• Output Bias Voltage -12 ±3.0 VDC

• Dynamic Output Impedance Less than 2400 Ω

• Operating Temperature -51°C to +121°C (-60°F to +250°F)

• Connector Type 2-pin MIL-C-5015 top-exit interface

Industrial Applications and Operational Benefits

The 330500-07-04 Velomitor is a fundamental component for Turbine Supervisory Instrumentation (TSI) and general machinery protection. Its ability to be mounted at any orientation—vertical, horizontal, or at an angle—makes it highly versatile for various machine geometries.

• Steam and Gas Turbines Monitoring casing vibration to identify rotor-generated faults in power generation facilities.

• Centrifugal Compressors Tracking absolute vibration on bearing housings to prevent catastrophic failures.

• Balance-of-Plant (BoP) Equipment Providing cost-effective protection for large motors, blowers, and pumps.

• Hazardous Process Zones Utilizing its ATEX/IECEx certifications for safe operation in oil, gas, and chemical refineries.

By providing a stable velocity output directly to Bently Nevada 3500/42M or 1900/65A monitors, this sensor supports proactive maintenance strategies. The solid-state design ensures long-term calibration stability, reducing the total cost of ownership while maximizing the availability of critical industrial assets.