Configured for axial shaft position measurement in rotating machinery monitoring systems, the Bently Nevada 991-50-XX-01-00 (991-50-XX-01-00 991 Thrust Transmitter) provides direct physical signal conversion from a 3300 NSv proximity probe input to a proportional 4-20 mA output.
Hardware Specifications
Parameter
Specification
Model
991-50-XX-01-00
Brand
Bently Nevada
Origin
USA
Weight
Approx. 0.43 kg
Dimensions
Compact DIN-rail mounting enclosure
Operating Temp
-35 deg C to +85 deg C
Power Consumption
Loop-powered, 12 to 35 VDC supply
Product Type
Thrust Transmitter
Measurement Function
Axial shaft displacement and thrust position monitoring
Input Sensor
Bently Nevada 3300 NSv proximity probe
Output Signal
4-20 mA DC proportional current output
Circuit Configuration
Two-wire transmitter
Mounting Type
DIN-rail mounting
Measurement Range
+/- 0.5 mm full-scale
Cable Interface
75 ohm coaxial probe cable system
Storage Temperature
-51 deg C to +100 deg C
Humidity Rating
100% condensing, non-submerged with connector protection
Application
Rotating machinery condition monitoring systems
Eddy-Current Probe Scaling and Rotor Dynamics Signal Processing
The Bently Nevada 991-50-XX-01-00 operates with eddy-current proximity measurement technology through the 3300 NSv probe system. The probe generates an electromagnetic field, and shaft movement changes the probe impedance to provide proportional displacement information.
The transmitter performs probe signal conditioning and eddy-current probe scaling before converting the measured axial displacement into a 4-20 mA output signal. Therefore, external signal conversion equipment is not required for connection to compatible monitoring inputs.
The installation process includes gap voltage validation based on Bently Nevada probe operating requirements. The system uses controlled probe excitation and signal processing methods to maintain measurement accuracy during rotor axial movement monitoring.
Frequently Asked Questions
Q: What input sensor is required for the 991-50-XX-01-00 transmitter? A: The transmitter requires a compatible Bently Nevada 3300 NSv proximity probe with the matching cable system for axial position measurement.
Q: What electrical output does the 991-50-XX-01-00 provide? A: The unit provides a two-wire 4-20 mA DC proportional output representing measured thrust position.
Q: How should the transmitter be mounted in a control cabinet? A: The transmitter is designed for DIN-rail mounting inside an industrial control enclosure with appropriate wiring separation and cable routing practices.
Field Installation Guidelines
Verify compatibility between the transmitter, proximity probe, and extension cable before commissioning.
Confirm correct probe installation position and perform gap voltage validation during setup.
Route probe cables separately from high-current power wiring to reduce electrical interference.
Connect the 4-20 mA loop according to the receiving PLC, DCS, or machinery monitoring input requirements.
Maintain proper shielding and grounding practices for low-level proximity measurement signals.
Inspect terminal connections and loop current values after installation to confirm correct signal transmission.
