Description
Bently Nevada 3300/40-13-01-01-00-00 Eccentricity Monitor
The Bently Nevada 3300/40-13-01-01-00-00, also cataloged as the 3300/40 Eccentricity Monitor, operates as a dedicated hardware component for low-speed rotor bow measurement within the Bently Nevada 3300 TSI system. It acquires continuous displacement data from eddy-current proximity probes during turning gear operation to determine shaft eccentricity in microns peak-to-peak.
Suffix Breakdown & Model Matrix
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Option Code
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Description
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Selection
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3300/40
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Product Type
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Eccentricity Monitor
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-13
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Full-scale Range
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0 to 250 um pp
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-01
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Transducer Input
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7200 / 8 mm Proximitor System (200 mV/mil)
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-01
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Alarm Relay Option
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Epoxy-sealed relays
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-00
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Agency Approval
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Not required
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-00
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Safety Barrier Option
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None
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Hardware Specifications
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Parameter
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Specification
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Model Brand
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Bently Nevada
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Origin
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USA
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Weight
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Approx. 0.45 kg
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Dimensions
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241.3 mm x 114.3 mm x 25.4 mm
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Operating Temp
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0 degC to +65 degC
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Power Consumption
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7.7 W typical
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Input Signal
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0 to -10 VDC nominal gap voltage
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Transducer Supply
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-24 VDC
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Accuracy
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±1% of full scale at +25 degC
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Outputs
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Buffered transducer outputs, recorder output configurable for 4-20 mA, 0 to -10 VDC, or 1 to 5 VDC
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Eddy-Current Probe Scaling and Rotor Dynamics Alignment
The 3300/40-13-01-01-00-00 applies fixed 200 mV/mil scaling for direct correlation with 8 mm eddy-current probe systems. Gap voltage validation targets -10 VDC under static conditions to ensure linear displacement measurement. Rotor dynamics tracking aligns eccentricity alarms with defined turnover speeds, suppressing false trips caused by oil film effects at higher RPM ranges. Cross-talk suppression logic prevents interference between dual-probe channels during low-speed operation.
Frequently Asked Questions
Q: Does the monitor support hot-swap replacement in a live 3300 rack?
A: No. Removal or insertion must occur only after rack power-down to prevent backplane transient damage.
Q: What is the minimum rotational speed for valid eccentricity readings?
A: Measurement accuracy is maintained down to 1 RPM provided the probe gap voltage remains within calibration limits.
Q: Are the alarm relays latching or non-latching?
A: Relays are non-latching and reset automatically once monitored values fall below trip thresholds.
Field Installation Guidelines
Mount the module in a standard 3300 rack slot with proper EMC grounding. Use shielded twisted-pair cable for transducer connections, terminating shield drain wires directly to rack ground terminals. Maintain probe mounting perpendicular to the shaft surface with target area free from machining marks or debris. Verify gap voltage before commissioning by measuring DC bias at the probe tip. Ensure all unused I/O terminals are capped to prevent contamination ingress.
