Description
Key Technical Specifications
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Model Number: 330103-00-06-50-01-00
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Manufacturer: Bently Nevada (Baker Hughes)
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Measurement Range: 0-6mm (0-236 mils) linear displacement
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Output Signal: -18V to -2V DC (proportional to target displacement, 1V/3mm sensitivity)
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Frequency Response: 0-10 kHz (covers most machinery vibration frequencies)
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Target Material: Ferrous metals (steel, cast iron; non-ferrous requires special calibration)
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Probe Length: 5 inches (127mm)
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Thread Size: M10 x 1.5 (metric, for mounting bracket attachment)
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Operating Temperature: -34°C to +177°C (probe), -29°C to +66°C (extension cable)
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Supply Voltage: -24V DC (±10%, from 3500 monitor or power supply)
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Electrical Isolation: 500Vrms (probe-to-cable, per IEC 60664-1)
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Weight: 0.32kg (probe only)
Bently Nevada 330103-00-06-50-01-00
Field Application & Problem Solved
In the field, small-to-medium rotating machinery—think pump shafts, small turbine rotors, or compressor impellers—demand precise displacement data, but space constraints and tight clearances rule out bulkier sensors. The biggest headache with older 18mm-range units here is overkill: their larger probes and wider measurement range pick up unnecessary noise from adjacent components, while contact-based LVDTs wear out in greasy pump environments. This 6mm-range sensor solves that by fitting into tight spots (e.g., between bearing housings) and delivering focused data. You’ll find it on boiler feedwater pumps (tracking impeller axial shift), small gas turbines (monitoring rotor bow), or HVAC compressors (detecting bearing wear). Its core value is precision in compact form: the 6mm range matches typical small-machine gaps (0.1-3mm), and the 5-inch probe slips into cramped brackets where 10-inch models can’t. For example, in a wastewater plant’s submersible pump, it caught a 0.2mm shaft migration caused by bearing fretting—flagging the issue before the impeller hit the volute. The M10x1.5 thread and 50 suffix (5-inch length) align with standard Bently brackets (330130), cutting installation time by 30% vs. custom mounts.
Installation & Maintenance Pitfalls (Expert Tips)
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Incorrect Probe Gap for Small Ranges: Rookies use the 1-1.5mm gap standard for 18mm sensors. For 6mm range, set initial gap to 0.8-1.0mm (via feeler gauge)—too wide loses sensitivity to 0.1mm shifts, too tight risks rubbing in tight clearances. Lock with a jam nut to prevent vibration loosening.
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Ignoring Cable Stiffness: The 5-inch probe uses a shorter, stiffer cable. Route it carefully around brackets—sharp bends (>90°) can stress the internal conductor. I’ve seen a paper mill pump sensor fail after 6 months due to a 120° bend near the motor.
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Skipping Target Surface Finish Check: Small shafts (e.g., 1-inch diameter) often have rougher surfaces. Polish the target area to Ra ≤ 1.6μm (63 micro-inches) with emery cloth—pitting adds 0.05mm error, masking real displacement.
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Using Non-Ferrous Targets Uncalibrated: Aluminum pump shafts are common. Always order the NF (non-ferrous) variant or apply a 0.5mm steel shim to the target—without it, the sensor reads 30% low, as I found in a Texas chemical plant.
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Exceeding Max Cable Length: Short probe = shorter max cable (15m vs. 30m for 10-inch). Longer runs attenuate the -18V signal—if you need 20m, add a Bently 330180 repeater. A Louisiana refinery learned this the hard way with a 25m run that dropped signal to -12V.
Bently Nevada 330103-00-06-50-01-00
Technical Deep Dive & Overview
The 330103-00-06-50-01-00 is a Proximitor eddy current sensor from Bently’s 3300 Series, built for tight-clearance displacement measurement. It works via electromagnetic induction: a high-frequency oscillator in the 5-inch probe generates a magnetic field; as a ferrous shaft approaches, eddy currents form in the target, altering the coil’s impedance. This change is linearly converted to a voltage output (-18V at 6mm gap, -2V at 0mm). The 6mm range uses a compact coil design for higher sensitivity (1V/3mm) in small gaps, while the M10x1.5 thread ensures rigid mounting to avoid “soft foot” resonance. It pairs with Bently 3500/42M monitors to provide shaft orbit plots and displacement trends—critical for small-machine predictive maintenance. In short, it’s the “precision eye” for compact machinery: small enough to fit, sharp enough to catch trouble.
