Description
Bently Nevada 3300/50 Tachometer Monitor Module
The Bently Nevada 3300/50-02-01-00-00 also cataloged as the 3300/50 Tachometer Monitor Module operates as a dedicated hardware component for zero-speed detection and shaft rotational speed processing within the 3300 monitoring rack system. Configured for direct tachometer signal conditioning, the Bently Nevada 3300/50-02-01-00-00 (3300/50 Tachometer Monitor Module) provides direct electrical execution of proximity probe and magnetic pickup inputs for low-speed threshold evaluation.
Suffix Breakdown & Model Matrix
| Code Segment |
Description |
Configuration |
| -02 |
Tachometer Type |
Zero Speed Tachometer |
| -01 |
Relay Output |
5 A Epoxy-Sealed SPDT Relays |
| -00 |
Agency Approval |
None |
| -00 |
Safety Barriers |
Not Installed |
Hardware Specifications
| Parameter |
Specification |
| ModelBrand |
Bently Nevada 3300/50-02-01-00-00 |
| Origin |
USA |
| Weight |
1.5 kg |
| Dimensions |
51 mm x 203 mm x 330 mm |
| OperatingTemp |
-20 degC to +65 degC |
| PowerConsumption |
2.5 W |
| Input Channels |
Up to 2 transducer inputs |
| Compatible Sensors |
3300 / 7200 / 3000 proximity probes, magnetic pickups |
| Input Impedance |
10 kOhm nominal |
| Speed Range |
1 to 99999 rpm (system dependent) |
| Output Signal |
4-20 mA / voltage output selectable |
| Relay Output |
SPDT, 5 A epoxy sealed |
Eddy-Current Probe Scaling and Signal Integrity Control
The Bently Nevada 3300/50 module applies eddy-current proximity probe scaling based on calibrated gap voltage validation referenced to negative DC bias targets (commonly -10 VDC operating region in probe conditioning circuits). Signal linearization is maintained through internal conversion logic aligned with rotor dynamic displacement interpretation. Cross-talk suppression is implemented at the channel conditioning stage to reduce phase contamination between redundant tachometer inputs, particularly when dual probe voting logic is enabled. Magnetic pickup inputs exhibit reduced fidelity at near-zero rotational velocity due to coil amplitude decay, making eddy-current transducer systems the preferred measurement source for zero-speed confirmation.
Frequently Asked Questions
Q: Does the 3300/50 support hot-swapping in the rack system?
A: The module is not designed for live insertion under load conditions. Backplane power should be removed prior to installation or removal to avoid transient signal corruption.
Q: What is the input redundancy behavior between dual channels?
A: The module applies internal voting logic between two independent transducer inputs. Discrepancy handling is governed by threshold comparison and fails to a conservative zero-speed state under signal loss conditions.
Q: Can magnetic pickups be used for zero-speed detection?
A: Magnetic pickups are supported but exhibit reduced resolution near zero rpm due to low induced voltage amplitude, limiting accuracy in true zero-speed conditions.
Field Installation Guidelines
Ensure backplane power isolation before inserting the module into the 3300 rack. Maintain shield continuity for all proximity probe signal cables and terminate shields at a single-point ground to prevent ground loop formation. Signal wiring should be routed separately from high-voltage or VFD conductors to minimize electromagnetic interference coupling. Verify probe gap calibration using manufacturer-specified reference targets prior to commissioning. All terminal connections must maintain mechanical torque retention to prevent micro-disconnection under vibration environments.
