Bently Nevada 330500-01-00 Velomitor Sensor

Product Introduction

The Bently Nevada 330500-01-00 Velomitor Piezo-velocity Sensor offers a trusted solution for continuous machinery vibration monitoring. This model specifically features the -01 mounting thread option, which provides a 1/2-20 UNF connection for installations requiring this specific thread size. Engineered for durability, this sensor delivers accurate velocity measurements across a wide frequency range. Its piezoelectric sensing element requires no external power for signal conversion, simplifying the overall monitoring chain. Consequently, this sensor excels in protecting critical assets such as gas turbines, compressors, and large pumps.

Technical Specifications

Electrical Performance

The 330500-01-00 provides a standard sensitivity of 3.94 mV/mm/s (100 mV/in/s) with a ±5% tolerance. Its frequency response extends from 4.5 Hz to 5 kHz (270 cpm to 300 kcpm) at ±3.0 dB, while a tighter ±0.9 dB response applies from 6.0 Hz to 2.5 kHz (360 cpm to 150 kcpm). The output bias voltage is -12 ±3.0 VDC, referenced to Pin A, and the dynamic output impedance measures less than 2400 Ω. Additionally, the broadband noise floor remains at a nominal 0.004 mm/s (160 μin/s) rms, ensuring signal clarity.

Linearity and Range

This sensor exhibits excellent amplitude linearity of ±2% up to 152 mm/s (6 in/s) peak. It supports a full-scale velocity range of 1270 mm/s (50 in/s) peak. Furthermore, its transverse sensitivity is less than 5%, which minimizes cross-axis errors. The mounted resonant frequency exceeds 12 kHz, effectively keeping structural resonances from contaminating the measurement signal.

Environmental and Mechanical Specifications

Robust Operating Conditions

The Bently Nevada 330500-01-00 operates reliably across an extreme temperature range of -55°C to 121°C (-67°F to 250°F). It also survives mechanical shock up to 5,000 g peak and functions in 100% relative humidity environments thanks to its hermetically-sealed stainless steel housing. Moreover, the case is isolated from the internal circuitry to prevent ground loops, and magnetic field susceptibility is minimal at less than 51 min/s/gauss.

Physical Attributes

This sensor weighs just 142 grams (5.0 oz) and features a compact form factor with a diameter of 25.3 mm (0.995 in) and a height of 63.2 mm (2.49 in). The case material is 316L stainless steel, offering superior corrosion resistance. The connector is a hermetically-sealed 2-pin Mil-C-5015 type with a 316L stainless steel shell, ensuring long-term reliability in harsh environments.

Installation and Cable Guidelines

Mounting Instructions

The defining feature of this model is its -01 mounting thread option, which is a 1/2-20 UNF thread. This distinguishes it from the standard -00 option. The recommended mounting torque is between 32-46 kg cm (24-40 in-lb) maximum. Achieving the correct torque is essential for optimal frequency response and sensitivity. Pay attention to polarity as well: when the sensor case moves toward the connector, Pin A becomes positive relative to Pin B.

Cable Selection

For signal transmission, the 330500-01-00 supports a maximum cable length of 305 meters (1,000 feet) using Bently Nevada part number 02173006 without any signal degradation. Under specific conditions—50g vibration at 10 kHz with 200 pf/m cable capacitance—the recommended cable length is 208 feet (63m). Proper cable selection ensures that the sensor's output remains accurate and interference-free.

Compliance and Certifications

The 330500-01-00 complies with FCC Part 15 rules, the EMC Directive 2014/30/EU, and the RoHS Directive 2011/65/EU. It also holds DNV maritime certifications for ships, high-speed craft, and offshore structures. Crucially, this sensor carries hazardous area approvals including Ex ia IIC T4 and Class I, Division 1, Groups A, B, C, and D, with a T4 rating at -40°C ≤ Ta ≤ 100°C. Such extensive compliance makes it suitable for global deployment in safety-critical applications.

Packaging List

• 1 x Bently Nevada Velomitor Piezo-velocity Sensor (Model 330500-01-00)

• 1 x Installation and Wiring Guide

• 1 x Calibration Certificate (summary)

Note: We do not include formal compliance certificates or warranty documents in this standard packaging. Please request these separately if required.

Frequently Asked Questions (FAQ)

Q1: What differentiates the 330500-01-00 from the 330500-00-CN model?
The primary difference lies in the mounting thread and agency approval. The 330500-01-00 uses a 1/2-20 UNF thread and has no specific country certification (-00). In contrast, the -CN model uses a standard thread and carries country-specific approvals.

Q2: Is this sensor suitable for use in potentially explosive atmospheres?
Yes. It holds multiple hazardous area certifications, including Ex ia IIC T4 for Zone 0 applications and Class I, Division 1 for Groups A, B, C, and D. Always verify your specific area classification before installation.

Q3: Can I use this sensor with a third-party vibration monitor?
Yes, you can. The sensor provides a standard 100 mV/in/s velocity output with a -12 VDC bias voltage. Most industrial vibration monitors accept this signal, though we recommend confirming compatibility with your specific instrument.

Q4: What happens if I exceed the recommended cable length?
Exceeding 305 meters (1,000 feet) may introduce signal attenuation and increase susceptibility to electrical noise. Therefore, for optimal performance, you should strictly adhere to the specified cable length limits.

Q5: How do I ensure proper grounding to avoid measurement errors?
The sensor case is isolated to prevent ground loops. Consequently, the grounding point should be the monitoring system's common return. Follow the installation drawing (dwg 167537) for detailed wiring instructions to ensure accurate readings.