Description

The Bently Nevada 330500-07-04 operates as a high-performance, solid-state piezoelectric velocity sensor designed to measure absolute structural, casing, or bearing housing vibration. Unlike traditional moving-coil velocity transducers, this Velomitor embeds integrated internal conditioning electronics inside a rugged accelerometer-based design. Consequently, the sensor has no moving mechanical parts to degrade or wear out, allowing technicians to install the hardware at any mounting orientation angle (vertical, horizontal, or omnidirectional) without sacrificing precision.

Hardware Specifications

Transducer Electronics and Signal Processing

The Bently Nevada 330500-07-04 internally measures physical acceleration and automatically integrates that raw movement into an analog velocity voltage output. This velocity metric aligns directly with standard machine case tracking profiles, making it highly effective for catching common malfunctions like structural imbalance or rotor misalignment.

Integration Warning: Do not attempt to secondary-integrate the output of the 330500 to obtain displacement data. Doing so amplifies low-frequency electrical noise floor artifacts from the internal circuit and surrounding instrumentation, resulting in heavily corrupted, inaccurate displacement profiles.

Frequently Asked Questions

Q: What specific hardware configurations do the “-07” and “-04” option codes define?

A: The option code -07 specifies that the sensor includes a 3/8 – 24 UNF threaded mounting adapter stud to couple the flat base securely to the machine casing. Meanwhile, the option code -04 indicates comprehensive multiple-agency certifications, combining regional North American CSA safety standards and European ATEX explosion protection approvals into a single code for hazardous environments.

Q: Can this sensor handle long-distance field cable runs without losing signal strength?

A: Yes. Because the embedded electronics maintain a low dynamic output impedance (less than 2400 ohms), you can run up to 305 meters (1000 feet) of high-quality shielded twisted-pair cable from the sensor head to the monitor rack without signal attenuation.

Field Installation Guidelines

• Shielding and Ground Isolation: First, connect your 2-conductor shielded field wiring to the MIL-C-5015 top receptacle. Because the Velomitor features a case-isolated design, float the shield wire at the sensor end and land the drain terminal exclusively at the monitor instrument rack to isolate it from parasitic ground loop currents.
• Mechanical Mounting Surface: Machine the target location flat, smooth, and free of any residual layers of paint or rust. Use the included 3/8 – 24 UNF thread adapter stud to mount the base flush against the structural target.
• Torque Specifications: Always use a calibrated torque wrench to lock down the sensor housing. Tighten the base to a torque value between 3.6 to 4.5 N-m (32 to 40 in-lb). Overtightening can break the internal crystal bonding layers, while undertightening dampens the high-frequency response of the casing energy.