Description

Bently Nevada 330500-0300 Velomitor Piezoelectric Velocity Sensor

The Bently Nevada 330500-0300 is a high-precision Velomitor piezoelectric velocity sensor designed for comprehensive vibration monitoring of rotating machinery. Unlike traditional moving-coil velocity transducers, this solid-state sensor utilizes piezoelectric crystal technology to convert vibration into an electrical signal.¹ This design eliminates moving parts that are prone to mechanical wear, ensuring a significantly longer service life and superior frequency response. It is a critical component for monitoring casing vibration on pumps, motors, and compressors.²

Piezoelectric Design and Signal Processing

This Velomitor integrates internal electronics that process the raw piezoelectric charge into a standard velocity-proportional voltage output. Specifically, the 330500-0300 provides a sensitivity of 3.94 mV/mm/s (100 mV/in/s), allowing it to interface directly with Bently Nevada 3500 series monitors or distributed control systems.³ Furthermore, because the sensing element is solid-state, it can be mounted in any orientation without affecting measurement accuracy. As a result, maintenance teams can reliably detect early mechanical failures, such as unbalance or looseness, across a wide variety of machine geometries.

Technical Specification Matrix

Industrial Durability and Environmental Protection

Engineered for the most demanding industrial sectors, the 330500-0300 features a 316L stainless steel housing that is hermetically sealed to prevent the ingress of moisture or contaminants. Moreover, the sensor is designed to operate effectively in extreme thermal conditions, maintaining linear accuracy from arctic cold to high-heat environments. In addition, the internal electronics are shielded against electromagnetic interference (EMI), which is vital for maintaining signal clarity near large motors and variable frequency drives. Therefore, this velocity sensor is the industry standard for reliable, low-maintenance vibration monitoring in power plants and refineries.

FAQ

What is the advantage of a Velomitor over a standard accelerometer?

A Velomitor measures velocity directly, which is the most common parameter used for determining the overall health of rotating machinery. Specifically, while accelerometers are better for high-frequency gear or bearing faults, the 330500-0300 provides a clearer picture of destructive forces related to unbalance and misalignment.

Does this sensor require an external power supply?

Yes, the sensor requires a constant current power source, typically provided by the monitor rack or an interface module. Furthermore, the output is a two-wire system where the signal is superimposed on the DC power line. Accordingly, you must ensure your monitoring system is compatible with constant-current piezoelectric sensors.

Can the 330500-0300 be used in hazardous locations?

The specific 0300 model variant should be checked against the latest data sheet for localized approvals. Consequently, Bently Nevada offers versions with ATEX, IECEx, and CSA certifications for explosive atmospheres. As a result, it is widely used in hazardous zones within the petrochemical and natural gas industries.4