Description
Bently Nevada 3300/20-12-01-02-00-00 Dual Thrust Position Monitor
Configured for axial shaft position monitoring in Bently Nevada 3300 machinery protection system, the Bently Nevada 3300/20-12-01-02-00-00 (3300/20 Dual Thrust Position Monitor) provides direct physical/electrical execution.
The module processes two independent channels of thrust (axial) displacement using proximity probe inputs from 3300 or 7200 eddy-current transducer systems. It converts gap-voltage proportional signals into calibrated axial position values referenced around a centered zero scale. Internal comparator logic evaluates Alert and Danger thresholds per channel and drives relay outputs for protection interlocking and external control systems.
Suffix Breakdown & Model Matrix
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3300/20: Dual Thrust Position Monitor platform
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-12: Full-scale range configured for 1.0 mm to 0 to 1.0 mm (40 mils to 0 to 40 mils)
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-01: Transducer input compatibility for 3300 / 7200 proximity systems (200 mV/mil, 7.87 V/mm)
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-02: Hermetically sealed alarm relay option
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-00: No agency approval configuration
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-00: No internal safety barriers installed
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-00: Trip multiply function not enabled
Hardware Specifications
| Parameter |
Specification |
| ModelBrand |
Bently Nevada 3300/20-12-01-02-00-00 |
| Origin |
USA |
| Weight |
1.0 kg (approx) |
| Dimensions |
3300 rack compatible module format |
| OperatingTemp |
0 degC to +65 degC |
| PowerConsumption |
Backplane powered (3300 rack supply dependent) |
| Channels |
2 independent thrust channels |
| Input Type |
Eddy-current proximity probe system |
| Input Sensitivity |
200 mV/mil (7.87 V/mm) |
| Frequency Response |
DC to 20 Hz |
| Full Scale Range |
1.0 mm to 0 to 1.0 mm |
| Outputs |
Analog recorder outputs, buffered probe outputs |
| Alarm Relays |
Alert and Danger, channel independent |
Eddy-Current Scaling and Gap Voltage Validation
The module operates on eddy-current proximity probe scaling where shaft displacement is derived from gap voltage variation across the probe target surface. Input linearization is referenced to calibrated sensitivity constants (200 mV/mil). Internal validation circuitry checks gap voltage stability against expected transducer operating window (typically centered around -10 VDC bias region in 3300 series architecture). Signal conditioning minimizes cross-channel coupling effects during dual-channel thrust measurement, maintaining separation between redundant axial measurement paths.
Frequently Asked Questions
Q: Can the module process dynamic vibration signals?
A: No. Bandwidth is limited to DC to 20 Hz, intended for slow axial displacement and thrust tracking only.
Q: What is the behavior during probe signal loss?
A: Loss of transducer input forces channel fault state, de-energizing associated relay outputs depending on configured alarm logic.
Q: Are the two channels electrically isolated?
A: Channels operate independently but share common rack backplane power reference; isolation is not full galvanic separation.
Field Installation Guidelines
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Install module only in Bently Nevada 3300 series rack backplane slot with stable grounding reference
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Maintain coaxial probe cable shielding continuity from proximity probe to monitor input terminal
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Avoid routing proximity signal cables parallel to high-voltage or switching conductors
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Ensure probe-to-target air gap is within calibrated linear range before commissioning
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Verify ALERT and DANGER relay wiring continuity before enabling trip logic
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Perform system OK check prior to machine start to validate probe, cable, and monitor integrity
