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The UNS 4881B is a high-performance control interface module developed for industrial power automation systems. Designed to operate as part of a larger excitation or control architecture, it functions as a communication and control processor—handling signal coordination, data processing, and real-time communication across system components.
The module is part of the UNS series, a family of industrial-grade interface boards and control modules developed to meet the demands of power generation, transmission, and advanced automation. The UNS 4881B version is typically used in excitation control systems, often playing a vital role in the management of voltage regulation and generator behavior.
Excitation System Control in power generation plants
Voltage Regulation in synchronous generators
Signal Interface Layer in distributed control systems (DCS)
Industrial Automation Communication Gateways
Legacy System Integration and Upgrades
Condition Monitoring and Real-Time Data Processing
High Reliability: Proven performance in critical infrastructure systems such as power plants and substations.
Modular Design: Easy to replace and upgrade within existing rack-mount systems.
Precision Control: Ensures accurate voltage regulation and consistent generator response.
Robust Build: Designed for harsh industrial environments with wide temperature and vibration tolerance.
Seamless Integration: Interfaces effortlessly with other UNS series modules and broader ABB platforms.
Brand: ABB
Series: UNS Series
Category: Control Interface / Excitation System Module
Part Number: 3BHE009949R0001
Model Code: UNS 4881B
| Parameter | Specification |
|---|---|
| Model | UNS 4881B |
| Part Number | 3BHE009949R0001 |
| Series | UNS Series |
| Function | Excitation System Control Module |
| Input Voltage | 24V DC (nominal) |
| Power Consumption | < 30W |
| Mounting Type | Rack / Panel Mount |
| Operating Temperature | –10°C to +55°C |
| Cooling | Passive air-cooled |
| Compliance | CE / RoHS / UL |
| Communication Ports | RS-232 / CAN / Internal bus |
| Dimensions (L×W×H) | 290 mm × 220 mm × 45 mm |
| Weight | 1.25 kg |
| Model | Function / Description | Dimensions (mm) | Weight (kg) |
|---|---|---|---|
| UNS 4880A | Predecessor model, signal interface unit | 290 × 220 × 45 | 1.20 |
| UNS 0880A-P | Analog signal interface module | 280 × 200 × 40 | 1.15 |
| UNS 0885A-P | Compact I/O processing unit | 270 × 190 × 38 | 1.10 |
| UNS 0890A-P | Analog acquisition with processing support | 300 × 220 × 50 | 1.50 |
| UNS 4890B | Advanced excitation control module | 295 × 225 × 45 | 1.35 |
| Model | Application Area | Dimensions (mm) | Weight (kg) |
|---|---|---|---|
| PM866AK01 | CPU Controller for AC800M series | 185 × 125 × 75 | 0.80 |
| CI854AK01 | PROFIBUS DP Interface Module | 180 × 110 × 60 | 0.70 |
| CI873K01 | Ethernet/IP Interface Unit | 175 × 100 × 60 | 0.65 |
| DSQC679 | Robotics Communication Interface | 160 × 100 × 40 | 0.60 |
| PM864AK01 | Advanced Control CPU Unit | 200 × 130 × 90 | 0.85 |
Q1: What is the primary function of the UNS 4881B?
A1: It serves as an excitation system control module, managing signal flow and voltage regulation in industrial generators.
Q2: Is the UNS 4881B compatible with other ABB modules?
A2: Yes, it integrates seamlessly within the UNS series and broader ABB automation platforms.
Q3: What voltage does it operate on?
A3: The module is typically powered by a 24V DC supply.
Q4: How much power does it consume?
A4: It consumes less than 30W during operation.
Q5: What are its dimensions and weight?
A5: The module measures 290 mm × 220 mm × 45 mm and weighs approximately 1.25 kg.
Q6: Can it be mounted on standard racks?
A6: Yes, the UNS 4881B is designed for standard panel or rack mounting.
Q7: What are its typical use environments?
A7: It is used in power plants, substations, and heavy industrial automation setups.
Q8: Is the module suitable for high-temperature environments?
A8: Yes, it operates reliably between –10°C and +55°C.
Q9: Is it easy to replace or upgrade this module?
A9: Yes, the modular design allows for fast replacement or system upgrades.
Q10: What communication interfaces are available on this unit?
A10: Common interfaces include RS-232, CAN, and internal backplane bus.
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