Bently Nevada 330101 Proximity Probes

Technical Dossier

Product Details And Specifications

Bently Nevada 330101 Series: Comprehensive Proximity Probe Range and Technical Overview

The Bently Nevada 330101 Series comprises eddy-current proximity probes designed for continuous, non-contact measurement of shaft radial vibration, axial position, and differential expansion in rotating machinery. These probes are a core sensing element within the 3300 XL and legacy 3300 Series monitoring systems, and are installed across global heavy industry sectors including petrochemical refineries, nuclear power stations, LNG terminals, offshore platforms, and combined-cycle power plants. The 330101 probe interfaces with a dedicated extension cable (330130 Series) and proximitor/oscillator-demodulator (330180 Series) to form a complete measurement chain. The series operates on the eddy-current principle at a nominal frequency of 1.0 MHz, providing a linear output of −7.87 V/mm (−200 mV/mil) within a calibrated range of 0.25 mm to 2.26 mm (10 to 89 mil). The 330101 is API 670 compliant and is the standard probe for turbomachinery protection systems worldwide.

The Evolution of 330101 Architecture

The 330101 Series was introduced as part of Bently Nevada's 3300 monitoring platform, which succeeded the earlier 7200 Series probes. The 7200 Series operated at a different frequency (500 kHz) and used a different calibration curve, making it incompatible with 3300 Series proximitors without recalibration. The 330101 standardized on a 1.0 MHz carrier frequency and a −200 mV/mil sensitivity, establishing a consistent measurement chain across the 3300 and 3300 XL platforms.

With the introduction of the System 1 condition monitoring software and the 3500 Series rack, Bently Nevada maintained backward compatibility with 330101 probes through the 330180 proximitor, allowing existing probe installations to feed data into modern digital monitoring architectures without physical replacement. The 330101 probe tip diameter is 8 mm, and the series is available in armored and non-armored cable configurations, with stainless steel and PEEK tip materials for high-temperature and chemically aggressive environments.

330101 Full Catalog & Functionalities (SKU List)

Proximity Probes — 8 mm Tip, Standard Configuration

• 330101-00-06-10-02-00: 8 mm probe, 15 cm (6 in) cable, 3/8-24 UNF thread, non-armored, standard temp
• 330101-00-06-10-02-05: 8 mm probe, 15 cm cable, 3/8-24 UNF, non-armored, ATEX/IECEx certified
• 330101-00-12-10-02-00: 8 mm probe, 30 cm (12 in) cable, 3/8-24 UNF, non-armored, standard temp
• 330101-00-18-10-02-00: 8 mm probe, 45 cm (18 in) cable, 3/8-24 UNF, non-armored, standard temp
• 330101-00-30-10-02-00: 8 mm probe, 76 cm (30 in) cable, 3/8-24 UNF, non-armored, standard temp
• 330101-00-49-10-02-00: 8 mm probe, 125 cm (49 in) cable, 3/8-24 UNF, non-armored, standard temp
• 330101-00-49-10-12-05: 8 mm probe, 125 cm cable, 3/8-24 UNF, armored cable, ATEX/IECEx certified

Proximity Probes — 8 mm Tip, High-Temperature Configuration

• 330101-00-06-10-02-CN: 8 mm probe, 15 cm cable, high-temp rated to 177°C, non-armored
• 330101-00-12-10-02-CN: 8 mm probe, 30 cm cable, high-temp rated to 177°C, non-armored
• 330101-00-30-10-02-CN: 8 mm probe, 76 cm cable, high-temp rated to 177°C, non-armored
• 330101-00-49-10-02-CN: 8 mm probe, 125 cm cable, high-temp rated to 177°C, non-armored

Proximity Probes — 5 mm Tip, Narrow-Access Configuration

• 330101-00-06-05-02-00: 5 mm probe, 15 cm cable, M10 thread, non-armored, standard temp
• 330101-00-12-05-02-00: 5 mm probe, 30 cm cable, M10 thread, non-armored, standard temp
• 330101-00-30-05-02-00: 5 mm probe, 76 cm cable, M10 thread, non-armored, standard temp
• 330101-00-49-05-02-00: 5 mm probe, 125 cm cable, M10 thread, non-armored, standard temp
• 330101-00-49-05-12-05: 5 mm probe, 125 cm cable, M10 thread, armored cable, ATEX/IECEx certified

Sourcing Hard-to-Find & Obsolete 330101 Parts

For plants operating under API 670 Fourth or Fifth Edition requirements, DriveKNMS can supply 330101 probes with full traceability documentation, including calibration certificates traceable to NIST standards. We support emergency urgent RFQ handling for critical spares and can provide kitted replacement sets (probe + extension cable + proximitor) to minimize installation time during unplanned outages.

Quality Control for the 330101 Range

Each 330101 probe processed by DriveKNMS undergoes a structured inspection and functional test protocol before dispatch:

• Dimensional inspection: Probe tip diameter, thread pitch (3/8-24 UNF or M10), and cable length verified against model number specification.
• Coil resistance measurement: DC resistance of the probe coil measured and compared against Bently Nevada factory specification (nominal 8.0 Ω ± 10%).
• Gap vs. output linearity test: Probe connected to a 330180 proximitor on a calibrated gap fixture. Output voltage recorded at 0.25 mm, 0.50 mm, 1.00 mm, 1.50 mm, 2.00 mm, and 2.26 mm gaps. Linearity error must be within ±0.5% of full-scale range.
• Cable integrity check: Insulation resistance test at 500 VDC between center conductor and shield. Minimum acceptable: 100 MΩ.
• Connector inspection: BNC or integral connector examined for pin straightness, contact plating condition, and mechanical retention.
• ATEX/IECEx marking verification (for -05 suffix models): Certification markings, enclosure integrity, and cable gland condition verified against the applicable certificate of conformity.