Bently Nevada 330525-02 Velomitor XA Piezo-velocity Sensor Overview

The Bently Nevada 330525-02 is a Velomitor XA piezo-velocity sensor. This device measures absolute casing vibration on rotating machinery. Its design provides a direct velocity output without external signal conditioning. The Bently Nevada 330525-02 uses piezo-electric technology for reliable operation. Agency approval option 02 provides SIRA/CENELEC certification. Consequently, this sensor suits hazardous area installations across Europe and beyond.

Technical Specifications of 330525-02

Manufacturer: Bently Nevada (Baker Hughes Digital Solutions).

Part Number: Bently Nevada 330525-02.

Model: Velomitor XA Piezo-velocity Sensor.

Condition: New and original in factory packing.

Sensitivity: [Color: Red] 3.94 mV/mm/s (100 mV/in/s) ±5% [/Color].

Velocity Range: 1270 mm/s (50 in/s) peak.

Amplitude Linearity: ±2% to 152 mm/s (6 in/s) peak.

Transverse Sensitivity: Less than 5% of sensitivity.

Mounted Resonant Frequency: Greater than 12 kHz.

Broadband Noise Floor (4.5 Hz to 2 kHz): 0.004 mm/s (160 µin/s) rms nominal.

Frequency Response Characteristics

The Bently Nevada 330525-02 offers two frequency response ranges. From 4.5 to 2,000 Hz (270 to 120,000 cpm), accuracy is ±3.0 dB. For tighter requirements, 6.0 to 1,000 Hz (360 to 60,000 cpm) provides ±0.9 dB accuracy. This frequency range covers most industrial machinery vibration components. Consequently, this sensor suits steam turbines, gas turbines, compressors, and fans.

Electrical Specifications

DC Power Voltage: -22 to -30 VDC.

Bias Current: 2.5 to 6.0 mA.

Output Bias Voltage: -12 ± 3.0 VDC over temperature (referenced to Pin A).

Dynamic Output Impedance: Less than 2400 Ω.

Maximum Cable Length: 305 metres (1,000 feet) with Bently Nevada part number 02173007 cable. No signal degradation occurs at this length.

Grounding: Case isolated from signal ground.

Connector: 2-pin Mil-C-26482 hermetically sealed type. Shell material is 316L stainless steel.

Polarity: Pin A goes positive with respect to Pin B when sensor case motion is toward the connector.

Temperature Sensitivity and Environmental Specifications

Temperature Sensitivity: -14% to +7.5% typical over the operating temperature range.

Operating Temperature Range: -55°C to +121°C (-67°F to +250°F).

Shock Survivability: 5000 g peak maximum.

Relative Humidity: Up to 100% non-submerged condition. The case is hermetically sealed for full protection.

Magnetic Field Susceptibility: Less than 51 µin/s/gauss (50 gauss, 50-60 Hz).

Hazardous Area Approvals (Option 02 - SIRA/CENELEC)

The Bently Nevada 330525-02 carries multiple hazardous area certifications.

For Class I, Division 1, Groups A, B, C, D: Ex ia IIC T4 and AEx ia IIC T4 ratings apply. Also certified for Class II, Groups E, F, G, and Class III. Temperature rating is T4 at -40°C ≤ Ta ≤ 100°C.

For Class I, Division 2, Groups A, B, C, D: Ex nL IIC T4 and AEx nA IIC T4 ratings apply. Installation must follow drawing 167539. Temperature rating is T4 at -40°C ≤ Ta ≤ 100°C.

Physical Specifications

Weight: 156 g (5.5 oz) typical.

Diameter: 28 mm (1.1 in).

Height: 73.1 mm (2.88 in).

Case Material: 316L stainless steel (corrosion resistant).

Maximum Mounting Torque: 45 N-m (33 ft-lb).

Minimum Cable Bend Radius: 1.5 inches.

Key Features of 330525-02

The Bently Nevada 330525-02 provides direct velocity output for casing monitoring. Its hermetically sealed case protects against moisture and contaminants. Case isolation eliminates ground loop problems in industrial installations. The 316L stainless steel construction resists corrosion in harsh environments. SIRA/CENELEC approvals permit installation in explosive atmospheres. A wide temperature range from -55°C to +121°C suits extreme conditions. With 5000 g shock survivability, this sensor withstands severe mechanical impacts. The 305 metre maximum cable length allows remote mounting of monitoring electronics.

Installation Guidelines for 330525-02

Before starting, disconnect all power to the monitoring system. Clean the mounting surface to ensure proper contact. Apply a thin layer of couplant if required for your application. Mount the Bently Nevada 330525-02 using the provided mounting stud. Tighten to maximum 45 N-m (33 ft-lb) torque. Do not exceed this torque value. Connect the 2-pin Mil-C-26482 connector firmly. Ensure the connector locks securely in place. Route the cable with minimum 1.5 inch bend radius. Avoid sharp bends or cable strain. For hazardous area installations, follow drawing 167539 requirements. Verify the power supply provides -22 to -30 VDC. Check that bias current falls between 2.5 and 6.0 mA. Finally, confirm output bias voltage reads -12 ± 3.0 VDC.

Application Scenarios for 330525-02

The Bently Nevada 330525-02 monitors casing vibration on steam turbines. Gas turbines in power plants benefit from its wide frequency response. Compressors in refineries use the SIRA/CENELEC approval for safe operation. Fans and blowers in chemical plants rely on this velocity sensor. The 316L stainless steel case resists corrosion in offshore platforms. With -55°C rating, this sensor suits Arctic and cold climate installations. At 121°C maximum, it works in high temperature machinery environments. Consequently, the 330525-02 serves many industrial rotating machinery applications.

Package List for 330525-02

• One Bently Nevada 330525-02 Velomitor XA piezo-velocity sensor

• One mounting stud (pre-installed on sensor base)

• One product calibration certificate

• One installation drawing (reference 167539 for hazardous area use)

Common FAQs about the Bently Nevada 330525-02

Q1: What is the sensitivity of the 330525-02?

The Bently Nevada 330525-02 has a sensitivity of 100 mV/in/s (3.94 mV/mm/s) ±5%. This provides direct velocity output for casing vibration monitoring.

Q2: What hazardous area approvals does the 330525-02 carry?

Option code 02 provides SIRA/CENELEC approvals. Specifically, these include Ex ia IIC T4 for Zone 0 and Ex nL IIC T4 for Zone 2. Division 1 and Division 2 certifications are also included for North America. Installation must follow drawing 167539.

Q3: What is the frequency response of the 330525-02?

Two frequency response ranges are specified. For ±3.0 dB accuracy, use 4.5 to 2,000 Hz (270 to 120,000 cpm). For ±0.9 dB accuracy, use 6.0 to 1,000 Hz (360 to 60,000 cpm). Most industrial vibration monitoring falls within these ranges.

Q4: What power supply does the 330525-02 require?

The Bently Nevada 330525-02 requires -22 to -30 VDC power. Bias current consumption is 2.5 to 6.0 mA. Output bias voltage is -12 ± 3.0 VDC referenced to Pin A.

Q5: What is the maximum cable length for the 330525-02?

Maximum cable length is 305 metres (1,000 feet) with Bently Nevada part number 02173007 cable. No signal degradation occurs at this length. Therefore, remote mounting of monitoring electronics is practical and reliable.