Bently Nevada 330500-08-04 Velomitor Sensor

Product Introduction

The Bently Nevada 330500-08-04 offers exceptional absolute vibration measurement capabilities. This Velomitor Piezo-velocity Sensor transforms case velocity into a proportional electrical signal with high fidelity. Its piezoelectric sensing element ensures broad frequency response and outstanding long-term stability. Additionally, the sensor is manufactured in the U.S.A. under stringent quality control standards.

Specifically, the 330500-08-04 provides a sensitivity of 3.94 mV/mm/s (100 mV/in/s) with a ±5% tolerance. This standardized output simplifies integration with monitoring systems. Furthermore, the sensor features a case-isolated design to eliminate ground loop interference. Its hermetically-sealed 316L stainless steel housing protects against moisture and corrosive substances. This model also holds extensive hazardous area certifications for demanding industrial applications.

Technical Specifications

Performance and Frequency Response

The 330500-08-04 Velomitor delivers accurate measurements across a wide frequency band. Its frequency response spans 4.5 Hz to 5 kHz (270 cpm to 300 kcpm) at ±3.0 dB. Moreover, a tighter response of 6.0 Hz to 2.5 kHz (360 cpm to 150 kcpm) at ±0.9 dB ensures precision in critical ranges. The velocity range reaches 1270 mm/s (50 in/s) peak. Amplitude linearity holds within ±2% up to 152 mm/s (6 in/s) peak. The mounted resonant frequency exceeds 12 kHz. Therefore, this sensor captures both low-frequency machinery vibrations and higher-frequency components effectively.

Electrical Output Characteristics

The electrical performance of the 330500-08-04 is carefully specified. The output bias voltage measures -12 ±3.0 VDC, referenced to Pin A across the full temperature range. Dynamic output impedance remains less than 2400 Ω. The broadband noise floor, measured from 4.5 Hz to 5 kHz, is 0.004 mm/s (160 μin/s) rms nominal. This low noise floor ensures clear signal transmission. The maximum cable length reaches 305 metres (1,000 feet) with Bently Nevada cable (part number 02173006) without signal degradation. Polarity is clearly defined: when the case moves toward the connector, Pin A becomes positive relative to Pin B.

Environmental and Physical Specifications

This sensor withstands extreme conditions reliably. The operating temperature range extends from -55°C to 121°C (-67°F to 250°F). Shock survivability is rated at 5,000 g peak maximum. Relative humidity tolerance is 100% non-submerged, as the case is hermetically-sealed. Base strain sensitivity is 0.005 in/s/mstrain. Magnetic field susceptibility is less than 51 min/s/gauss (50 gauss, 50-60Hz). Physically, the sensor weighs 142 grams (5.0 oz) typical. Diameter measures 25.3 mm (0.995 in), and height is 63.2 mm (2.49 in). The case material is 316L stainless steel, and the connector is a 2-pin Mil-C-5015 hermetically-sealed type with a 316L stainless steel shell.

Mounting and Installation

The Bently Nevada 330500-08-04 features a 1/2 – 13 UNC mounting thread option. This standard thread size facilitates easy attachment to various machine surfaces. Apply mounting torque between 32-46 kg cm (24-40 in-lb) maximum for secure installation. Next, consider cable length requirements. Assuming maximum vibration of 50g at 10 kHz and cable capacitance of 200 pf/m, the recommended cable length is 208 ft (63m). Finally, observe polarity during wiring: Pin A is positive when motion is toward the connector.

Agency Approvals and Certifications

The 330500-08-04 Velomitor carries comprehensive approvals for global deployment. For hazardous areas, it holds Ex ia IIC T4 and AEx ia IIC T4 certifications. It is approved for Class I, Division 1, Groups A, B, C, and D. Additionally, it covers Class II, Groups E, F, G, and Class III. The T4 rating applies from -40°C ≤ Ta ≤ 100°C. It also holds Ex nL IIC T4 and AEx nA IIC T4 for Class I, Div 2, Groups A, B, C, D. Furthermore, it complies with FCC Part 15 rules. It meets EMC Directive 2014/30/EU and RoHS Directive 2011/65/EU. Maritime approvals include DNV rules for ships, high-speed craft, and offshore standards.

Packaging List

The product package includes the following items:

• Bently Nevada 330500-08-04 Velomitor Piezo-velocity Sensor (1 unit)

• Installation and wiring instruction sheet

Please note: Mounting hardware, cables, connectors, and certificates are not included and must be purchased separately.

Frequently Asked Questions (FAQ)

1. What is the sensitivity of the 330500-08-04 Velomitor?
The Bently Nevada 330500-08-04 has a sensitivity of 3.94 mV/mm/s, equivalent to 100 mV/in/s, with a tolerance of ±5%.

2. What mounting thread does this model use?
This sensor uses the -08 mounting thread option, which is 1/2 – 13 UNC. This standard thread fits many common mounting fixtures.

3. What hazardous area approvals does this sensor carry?
The 330500-08-04 holds Ex ia IIC T4 and AEx ia IIC T4 for Zone 1/Division 1, plus Ex nL IIC T4 and AEx nA IIC T4 for Zone 2/Division 2. It also includes DNV maritime approvals.

4. What is the operating temperature range for this device?
The 330500-08-04 operates reliably from -55°C to 121°C (-67°F to 250°F), suitable for extreme environments.

5. Is the sensor case grounded or isolated?
The 330500-08-04 features a case-isolated design. This prevents ground loop problems and improves signal integrity.