Compact OEM Thrust Monitoring Solution for Rotating Equipment
The Bently Nevada 991-25-XX-01-CN 991 Thrust Sensor is a compact axial position transmitter designed for continuous monitoring of shaft thrust movement in rotating machinery. Developed for OEM applications and industrial equipment manufacturers, this transmitter provides a reliable 4–20 mA proportional output representing shaft axial displacement, allowing easy connection with PLC, DCS, SCADA, and machinery control systems.
The 991 Series integrates Proximitor® sensor electronics directly into the transmitter housing, eliminating the requirement for a separate Proximitor module. The 991-25-XX-01-CN configuration features a 2.5 mm (25–0–25 mil) thrust measurement range, configurable transducer system length, 35 mm DIN-rail mounting, and a China (CN) approval configuration, making it an ideal choice for centrifugal compressors, small pumps, motors, fans, and other OEM rotating equipment where space efficiency and dependable monitoring are required.
Technical Specifications
| Parameter | Specification |
|---|
| Manufacturer | Bently Nevada |
| Model Number | 991-25-XX-01-CN |
| Product Type | 991 Thrust Sensor / Thrust Transmitter |
| Measurement Type | Shaft Axial Displacement (Thrust Position) |
| Measurement Range | 2.5 mm (25–0–25 mil) |
| Compatible Sensor | 3300 NSv Non-contacting Proximity Probe |
| System Length | XX (Configurable 5 m / 7 m system options) |
| Output Signal | 4–20 mA proportional analog output |
| Power Supply | +12 to +35 VDC |
| Loop Configuration | Two-wire loop powered |
| Mounting Type | 35 mm DIN-rail clips |
| Signal Conditioning | Integrated Proximitor® electronics |
| Diagnostic Output | Dynamic signal and gap voltage output |
| Maximum Loop Resistance | 1000 Ω at 35 VDC |
| Zero / Span Adjustment | External non-interacting adjustments |
| Operating Temperature | -35°C to +85°C |
| Housing Construction | Industrial sealed enclosure |
| Dimensions | Approx. 82 × 35 × 75 mm |
| Weight | Approx. 0.44 kg |
Industrial Applications
The 991-25-XX-01-CN is optimized for machinery manufacturers and end users requiring continuous thrust position monitoring in compact installations.
| Industry | Typical Equipment |
|---|
| Oil & Gas | Small centrifugal compressors, pumps |
| Petrochemical | Process machinery and auxiliary equipment |
| Power Generation | Turbine auxiliary systems |
| Manufacturing | Motors, fans, blowers |
| HVAC Systems | Industrial rotating equipment |
| OEM Machinery | Compressor packages and pump skids |
Common applications include:
-
Axial shaft position measurement
-
Thrust bearing condition monitoring
-
Machinery protection systems
-
Equipment health monitoring
-
Predictive maintenance programs
-
Automation system integration
Product Advantages
Designed for OEM Equipment Integration
The compact design of the 991 transmitter makes it especially suitable for OEM machinery where installation space is limited. It provides a complete thrust monitoring solution without requiring additional external signal conditioning hardware.
Integrated Proximitor® Technology
The built-in Proximitor electronics simplify system design by combining sensing interface and signal conversion in one compact unit. This reduces wiring requirements and improves installation efficiency.
Flexible System Length Options
The XX designation allows selection of the appropriate transducer system length, typically supporting different installation distances between the proximity probe and transmitter location.
Standard Industrial 4–20 mA Output
The transmitter provides a widely accepted 4–20 mA signal, enabling straightforward connection with industrial controllers, monitoring systems, and process automation platforms.
DIN-Rail Mounting Design
The 01 mounting configuration supports 35 mm DIN-rail installation, providing a convenient solution for control cabinets and OEM electrical panels.
Reliable Machinery Protection
By continuously measuring shaft axial movement, the transmitter helps identify abnormal thrust conditions before they develop into severe mechanical damage or unexpected downtime.
Technical FAQs
1. What is the Bently Nevada 991-25-XX-01-CN used for?
It is used for continuous monitoring of shaft axial displacement (thrust position) and provides a proportional 4–20 mA output for machinery monitoring systems.
2. What measurement range does this model provide?
The 25 option indicates a 2.5 mm (25–0–25 mil) thrust displacement measurement range.
3. Which probe is compatible with this transmitter?
The unit is designed to work with a Bently Nevada 3300 NSv proximity probe and extension cable system.
4. What does the "XX" code represent?
The XX designation represents the selectable transducer system length configuration, allowing adaptation to different machine installation requirements.
5. What does the "01" mounting option mean?
The 01 option indicates a 35 mm DIN-rail mounting configuration.
6. Does this model require an external Proximitor module?
No. The transmitter includes integrated Proximitor® electronics, reducing the need for additional signal conditioning equipment.
7. What output signal does the transmitter provide?
It provides a standard 4–20 mA proportional analog output corresponding to shaft axial position.
8. What power supply is required?
The transmitter requires a +12 to +35 VDC input supply at the transmitter terminals.
9. What diagnostic information is available?
The transmitter provides dynamic signal and gap voltage outputs for diagnostic evaluation of the proximity measurement system.
10. What equipment commonly uses this model?
It is commonly applied on centrifugal compressors, small pumps, motors, fans, and OEM rotating equipment requiring reliable thrust monitoring.
A DCS Q Co., Ltd. - PLC and DCS Industrial Control Equipment Wholesale
