Excellent PLC
| Company Information | ||||||||
| [email protected] | ||||||||
| Mobile | +8613666033393 | |||||||
| +8613666033393 | ||||||||
| 13666033393 | ||||||||
| Add | Room 1004, No. 62 Xiangxiu Li, Siming District, Xiamen City, Fujian Province, China | |||||||
Product Overview
The Bently Nevada 991 Thrust Transmitter is a loop-powered 4–20 mA transmitter designed to monitor shaft axial position (thrust position) in rotating machinery. It is especially suited for OEMs of centrifugal compressors, small pumps, motors, and fans. The device integrates signal conditioning and eliminates the need for a separate Proximitor, simplifying installation and reducing space requirements.
Key Features
-
Integrated Proximitor Sensor (no external unit needed)
-
4–20 mA loop-powered output
-
Compatible with 3300 NSv probes
-
Adjustable zero and span settings
-
Diagnostic output (PROX OUT) via coaxial connector
-
Built-in signal defeat and power-up inhibit circuits
-
Supports DIN rail or bulkhead mounting
-
Fully potted for use in humid environments (up to 100% RH)
Applications
-
Centrifugal compressors
-
Industrial fans and motors
-
OEM packaged rotating machinery
-
Small pump assemblies
-
Condition monitoring and diagnostics
-
Environments requiring compact axial position monitoring
Product Advantages
-
Simplifies thrust position monitoring in space-constrained installations
-
Provides reliable 4–20 mA signal directly to control systems
-
Minimizes wiring and hardware complexity
-
Supports diagnostics via PROX OUT output
-
Withstands harsh environmental conditions
-
Integrates easily into hazardous area applications (Zone 0, 2, Div 2)
Technical Specifications
| Parameter | Value |
|---|---|
| Input | 3300 NSv proximity probe & extension cable |
| Power Supply | +12 to +35 Vdc |
| Output | 4–20 mA loop signal |
| Accuracy | ±1.5% full scale (typical) |
| Max Loop Resistance | 1000 Ω at 35 Vdc |
| Signal Defeat (Not OK) Response | <3.6 mA within 100 μs |
| Linear Range | ±0.6 mm or ±25 mils |
| Temperature Range (Operating) | -35°C to +85°C (transmitter) |
| Humidity | 100% condensing |
| Mounting Options | DIN-rail or bulkhead |
| Dimensions | 100.1 x 73.9 x 53.3 mm |
| Weight | 0.43 kg |
Frequently Asked Questions (FAQ)
Q1: What type of probe is compatible with the 991 Thrust Transmitter?
A1: It is compatible with the 3300 NSv proximity probe and extension cable.
Q2: What output does the 991 provide?
A2: It provides a 4–20 mA loop signal proportional to axial thrust displacement.
Q3: Can the transmitter be used in hazardous areas?
A3: Yes, it is certified for use in ATEX Zone 0, Zone 2, and CSA Division 2 environments.
Q4: Does the device support diagnostics?
A4: Yes, via the PROX OUT terminal and coaxial connector for dynamic signal output.
Q5: Is external signal conditioning required?
A5: No, it has an integrated proximitor sensor that eliminates the need for an external unit.
Q6: How do you verify the output signal?
A6: A Test Input pin allows verification using a DC voltage source.
Q7: What happens in case of a probe fault?
A7: The Not OK/Signal Defeat function drops the signal below 3.6 mA to prevent false alarms.
Q8: What mounting options are available?
A8: DIN rail clips and bulkhead screws are available.
Q9: Is it suitable for humid environments?
A9: Yes, the unit is fully potted to tolerate 100% condensing humidity.
Q10: What is the recommended target material?
A10: The system is calibrated for AISI 4140 steel targets.
Related Models in the Same Series
| Model Number | Description | System Length | Mount Type | Approval |
|---|---|---|---|---|
| 991-06-50-01-00 | 0.6 mm range, 5 m cable, DIN mount | 5.0 m | DIN rail | No approval |
| 991-25-70-02-01 | 25 mils range, 7 m cable, bulkhead mount | 7.0 m | Bulkhead | CSA Div 2 |
| 991-06-70-03-00 | 0.6 mm range, 7 m cable, DIN+bulkhead | 7.0 m | Combo | No approval |
| 991-25-50-01-05 | 25 mils range, 5 m cable, DIN mount | 5.0 m | DIN rail | Full Cert. |
| 991-06-50-02-05 | 0.6 mm range, 5 m cable, bulkhead mount | 5.0 m | Bulkhead | Full Cert. |
| 991-25-70-03-05 | 25 mils range, 7 m cable, DIN+bulkhead | 7.0 m | Combo | Full Cert. |
Popular Models from Bently Nevada
| Model Number | Description | Signal Type | Application | Dimensions (mm) | Weight |
|---|---|---|---|---|---|
| 3500/42M-01-00 | Proximitor Seismic Monitor | Dynamic | Vibration Monitoring | 241 x 24 x 241 | 0.5 kg |
| 330104-00-06-10-11-00 | 3300 XL 8 mm Proximity Probe | Proximity | Shaft Vibration | 80 x 12 x 12 | 0.2 kg |
| 330180-91-CN | 3300 XL Proximitor Sensor | Dynamic | Displacement Monitoring | 62 x 48 x 25 | 0.25 kg |
| 3500/44M-02-00 | Aeroderivative GT Vibration Monitor | Dynamic | Turbomachinery Monitoring | 241 x 24 x 241 | 0.48 kg |
| 3500/25-01-01-00 | Keyphasor Module | Pulse | Speed/Phase Detection | 241 x 24 x 241 | 0.45 kg |
| 3500/22M-01-01-00 | Transient Data Interface (TDI) Module | Digital | System Communication | 241 x 24 x 241 | 0.45 kg |
