BENTLY 330750-60-RU Proximitor Sensor – 3300 XL eddy-current interface for vibration and position monitoring

The BENTLY 330750-60-RU is a 3300 XL series Proximitor Sensor used with 5 mm or 8 mm proximity probes and extension cables to measure shaft vibration and axial/rod position on critical rotating assets. From my experience, this model is chosen when teams want the familiar 3300 XL scale factor and stable bias (gap) voltage to tie into existing 3500 or other API 670-compliant monitors without re-engineering the panel. The “-RU” suffix typically indicates a regional documentation/language option; the core electrical performance remains the same as standard 3300 XL Proximitor variants.

Our Order Placement Process and Guarantees

• Warranty: 365 days
• Lead time: 1 week if in stock; no more than 1 month at the latest
• Payment: 50% advance payment; full payment prior to delivery
• Express options: FedEx, UPS, DHL

One thing I appreciate is how predictable the logistics are—teams can plan turnarounds with fewer surprises.

Key Features

• 3300 XL transducer compatibility – Works with standard 5 mm or 8 mm 3300 XL proximity probes and matching extension cables.
• Dual analog outputs – Dynamic vibration signal (AC) and DC gap (bias) voltage for position and clearance trending.
• Stable scale factor – Typically 200 mV/mil response with excellent linearity over the calibrated range for reliable diagnostics.
• Rugged, cabinet-ready – Encapsulated electronics with strong EMI immunity; suitable for industrial panels near high-energy equipment.
• API 670-friendly signals – Straightforward wiring into legacy and modern machine protection systems without protocol converters.
• Serviceable in the field – Probe gap can be set and verified quickly; bias voltage checks take minutes during startups.

Technical Specifications

Option note: “-RU” typically indicates a regional/language variant. Electrical and mechanical characteristics are the same as the standard 3300 XL Proximitor in most cases.

Application Fields

• Turbomachinery: steam/gas turbines (radial vibration, shaft axial position)
• Compressors and expanders: casing and bearing frame monitoring
• Pumps and fans: vibration and shaft position trending for predictive maintenance
• Gearboxes: gear mesh vibration and shaft runout observation
• Reciprocating machinery: rod drop and crosshead position with suitable probes

A maintenance lead told us they swapped this unit during a hot standby and saw the bias settle around -10.5 V within minutes—no rewiring needed, which saved a window in their startup plan.

Advantages & Value

• Reliability – The 3300 XL line is field-proven; bias stability and linearity reduce false trips.
• Compatibility – Drop-in with existing 3300 XL probes/cables and common protection racks (e.g., 3500 series).
• Cost control – Minimal engineering time; typically no panel redesign or new terminations.
• Technical support – Help with probe gapping, bias verification, and monitor scaling if you need it.

Installation & Maintenance

• Cabinet environment – Mount in a dry, ventilated instrument cabinet; keep away from high-heat zones and VFD cables when possible.
• Wiring – Use the matched 3300 XL probe and extension cable; maintain shielding and grounding per API 670 practices.
• Gapping – Set initial gap to the recommended bias voltage window; verify with a calibrated displacement simulator if available.
• Checks – Periodically confirm bias voltage and dynamic signal integrity; inspect connectors for looseness or corrosion.
• Spare strategy – Keep one spare Proximitor per train or per panel section to reduce MTTR during outages.

Quality & Certifications

• Certifications: CE and RoHS are typical for this series; many variants also carry UL/CSA and selected ATEX/IECEx approvals.
• Manufacturer quality system: Built under recognized quality controls aligned with ISO practices for industrial instrumentation.
• Warranty: 365 days (our supply warranty terms apply as stated above).