وصف
Bently Nevada 3300/48 Case Expansion Monitor
Configured for thermal casing displacement measurement in turbine supervisory systems, the Bently Nevada 3300/48-01-01-01-00 (3300/48 Case Expansion Monitor) provides dual-channel LVDT signal acquisition and direct electrical conversion for casing growth monitoring across 3300 machinery protection platforms.
Suffix Breakdown & Model Matrix
The 3300/48-01-01-01-00 configuration is factory-defined as follows:
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3300/48: Case Expansion Monitor base module
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-01: 0 to 1.0 inch full-scale measurement range
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-01: 1 inch LVDT input scaling (9 mV/mil standard)
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-01: Epoxy-sealed relay output stage
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-01: CSA/NRTL/C hazardous area certification option
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-00: No intrinsic safety barrier configuration
Hardware Specifications
| Parameter |
Specification |
| ModelBrand |
Bently Nevada 3300/48-01-01-01-00 |
| Weight |
1.0 kg (approx) |
| Dimensions |
Not specified in provided datasheet |
| OperatingTemp |
0 to 65 degC |
| Input Type |
2-channel DC LVDT |
| Input Impedance |
1.0 MOhm |
| Transducer Supply |
-24 VDC current-limited per channel |
| Scale Factor |
10 mV/mil, 9 mV/mil, 3.5 mV/mil selectable |
| Output Signals |
4-20 mA, 0 to -10 VDC, 1 to 5 VDC |
| Accuracy |
+/-0.33% typical, +/-1% max FS |
Mechanical Signal Conditioning Behavior (Bently Nevada Class Monitoring)
The Bently Nevada 3300/48 module implements dual LVDT-based displacement tracking with signal linearization referenced to eddy-current probe scaling principles used across Bently Nevada machinery protection systems. Channel processing includes gap voltage validation against calibrated excitation levels (nominal -10 VDC reference domain behavior in downstream signal conditioning chains). Cross-channel differential computation is used to suppress common-mode mechanical drift while isolating asymmetric casing expansion signatures. Signal integrity is maintained under rotor dynamic vibration influence by channel decoupling and internal crosstalk suppression filtering logic typical of 3300-series architecture.
Frequently Asked Questions
Q: Can the module operate with only one LVDT input active?
A: Yes. The unit can operate in independent channel mode, but differential alarm logic is disabled without valid dual-channel input correlation.
Q: Does the relay output change state during independent mode operation?
A: No. Alarm relay actuation is only enabled in differential measurement mode as defined by internal configuration logic.
Q: What is the limitation of backplane signal buffering?
A: Buffered outputs are impedance-isolated (100 ohm) and intended for monitoring only; they are not designed for load-driving external control circuits.
Field Installation Guidelines
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Maintain twisted shielded pair routing for both LVDT channels to reduce electromagnetic coupling
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Ensure LVDT excitation and return conductors are separated from high-power switching lines
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Ground cable shields at single-point earth reference only to avoid ground loop currents
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Verify correct jumper configuration for mV/mil scaling before commissioning
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Avoid mechanical stress on terminal blocks during enclosure mounting
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Ensure relay wiring complies with SPDT dry-contact isolation requirements
