330505-02-02-00 Bently Nevada Low Frequency Seismic Transducer

Product Overview

The 330505-02-02-00 is a high-performance seismic velocity sensor engineered by Bently Nevada for monitoring machinery with slow rotational speeds along the horizontal plane. Unlike vertical-only sensors, this transducer is specifically optimized for horizontal applications like hydro turbines and large industrial blowers, where vibration at frequencies as low as 0.5 Hz must be tracked for safety. By leveraging advanced seismic technology, it delivers high-resolution casing velocity data, enabling maintenance teams to identify imbalances and structural resonances before they cause unplanned outages.

Technical Configuration

The 330505-02-02-00 features a precise mechanical build dedicated to horizontal integration. The "-02" mounting angle option specifies a 90° horizontal orientation (±10°), ensuring maximum sensitivity for side-to-side mechanical movement. This model utilizes a 3/8-24 UNF-2B internal mounting thread and is supplied without an external adapter (-00 option). Encased in 300-series stainless steel with a hermetically sealed 2-pin Mil-C-5015 connector, it maintains superior signal integrity over long cable distances up to 305 meters when paired with Bently Nevada 3500/46M monitors.

Technical Specifications

Installation & Maintenance Guide

For accurate horizontal measurements, the 330505-02-02-00 must be mounted rigidly with a maximum torque of 46 kg·cm. The mounting base must be clean and flat to ensure high-frequency signal transmission. As a horizontal-mount sensor (-02), it must be oriented within ±10° of the horizontal axis. Technicians should use shielded cabling for the 305-meter maximum run to protect the low-frequency data from electromagnetic interference, ensuring the hermetic 2-pin connector is tightly sealed to maintain its 100% humidity rating.

Engineering Advantages

The 330505-02-02-00 is distinguished by its 50,000-hour MTBF and exceptional amplitude linearity (±3%). Its hermetically sealed stainless steel housing allows for continuous operation in saturated humidity environments common in hydro-power facilities. With a low output impedance of 100 Ω, this sensor facilitates clean signal transmission over significant distances, making it the industry standard for predictive maintenance on large-scale horizontal rotating assets.

Technical FAQs

Q1: Why is the 90° mounting angle calibration necessary?
A1: Horizontal sensors are internally balanced to compensate for gravity in a 90° orientation; using a vertical sensor horizontally would cause the seismic mass to bottom out, resulting in a "Not OK" status.

Q2: Does this sensor require an external power supply?
A2: It is powered by the -24 VDC supply provided by the Bently Nevada monitor, which results in the characteristic -12 VDC bias voltage for circuit health monitoring.

Q3: How does it handle extreme vibration levels?
A3: The 330505-02-02-00 features a shock survivability of 100g peak, protecting the internal piezo-seismic elements from damage during machine startup or transient surge conditions.