The SD833 is a high-performance, high-reliability 24V DC power module within the ABB AC 800M controller hardware platform and System 800xA. With a rated output of 10A/240W, this mid-power core model of the SD83x series achieves an excellent balance between power density, reliability, and cost. It is specifically designed to meet the demand for stable, clean DC power in medium to large-scale industrial automation systems, widely used in process control, factory automation, and scenarios requiring redundant power architectures.
The SD833 inherits all the core advantages of the SD83x series, including compliance with major global safety standards, simple DIN rail mounting, efficient switched-mode power supply technology, and comprehensive circuit protection. While it lacks the parallel capability and DC-OK relay of the SD834, its 10A output capacity is sufficient to drive complex control stations, making it an ideal choice for building cost-effective, high-reliability power solutions.
Within the AC 800M system architecture, the SD833 serves as a "main power supply unit," suitable for most industrial applications without extreme power demands:
Medium Single-System Power Supply: Provides stable power for systems containing one high-performance processor (e.g., PM865, PM891), several CEX-Bus communication interfaces (e.g., CI854, CI871), and multiple S800 I/O clusters. It is the standard power supply for many standard DCS stations or large PLC stations.
Standard Component for Redundant Power Systems: Paired with an SS823 or SS832 diode voting unit, two SD833 units can form a classic 1+1 redundant power supply system. This configuration provides high availability for AC 800M controllers, ensuring system operation continues unaffected by a single power supply failure, particularly suitable for process control loops with high continuity requirements.
Balance of Cost and Performance: Compared to the 5A SD832, the SD833 offers double the output capacity, meeting broader load requirements. Compared to the 20A SD834, it satisfies most applications while offering better cost-effectiveness and a more compact width (60mm), making it the most common choice for medium-sized projects.
Core Features and Benefits
Optimized Power Output: The 10A / 240W rated output capacity provides ample power for medium-sized automation systems, easily handling loads including multiple processor units, communication modules, and dozens of I/O modules. It avoids the capacity bottleneck of low-power supplies without incurring the extra cost of high-power systems.
High-Reliability Design:
Comprehensive Protection: Built-in overvoltage protection (OVP <39V), overcurrent protection, and short-circuit protection ensure effective protection for the power supply itself and downstream valuable equipment in case of output anomalies.
High Stability: Excellent line and load regulation (<70mV/<100mV) ensures output voltage remains highly stable during grid fluctuations or load changes, providing "clean" power for sensitive control electronics.
Soft-start: Effectively suppresses inrush current (<10A) at power-on, avoiding impact on upstream distribution and preventing nuisance tripping.
High Efficiency and Good Thermal Management: Conversion efficiency exceeding 91% means lower energy loss and operating costs, while significantly reducing the module's own heat generation. Combined with clear mounting clearance requirements (15mm lateral, 40mm vertical), this ensures long-term stable operation within the cabinet and extends service life.
Easy Integration and Maintenance:
Standard DIN Rail Mounting: Enables quick installation or removal without tools, greatly simplifying system integration and subsequent maintenance.
Clear Status Indication: Front panel equipped with an LED indicator for intuitive display of power status.
Strong Redundancy Support: As an ideal choice for building redundant power systems, two SD833 units paired with one SS823 or SS832 diode voting unit can form a highly available power system. If the primary supply fails, the backup supply can take over the load without interruption, significantly enhancing the overall control system's availability.
Stringent Safety and Quality Standards: Fully complies with major international safety standards (EN 50178, UL 508) and EMC standards. The output meets SELV/PELV safety extra-low voltage requirements, ensuring personnel and equipment safety. CE and UL markings guarantee product access to major global markets.
Installation, Configuration, and Wiring Guidelines
Safety First
Before performing any installation, it is mandatory to read and adhere to the "Safety Summary" in the AC 800M Controller Hardware user manual. Ensure the main power supply is completely disconnected and take appropriate electrostatic discharge (ESD) precautions.
Mechanical Installation Steps
Prepare Rail: Securely mount the standard TS 35/7.5 DIN rail onto the control cabinet backplane.
Plan Layout: Reserve the installation position for the SD833, ensuring a minimum clearance of at least 15mm on both left and right sides and at least 40mm above and below to meet heat dissipation requirements.
Mount Module: Align the top hook on the back of the SD833 module with the upper edge of the rail, press down and rotate the module until the bottom snap-fit latch engages the lower edge of the rail with an audible "click," confirming secure installation.
Electrical Wiring
Single Unit Operation:
Input Wiring:
Use wire with appropriate cross-section (recommended 1.5-2.5 mm²) to connect the AC line (L) and neutral (N) to the corresponding terminals.
The protective earth wire (PE) must be reliably connected to the module's PE terminal and ultimately to the cabinet grounding busbar.
In the input circuit, install a miniature circuit breaker (MCB, Characteristic B or C) rated 10-20A for protection.
Output Wiring:
Connect the output DC 24V (+) and 0V (M) to the power distribution terminals of the AC 800M system or directly to the power input terminals of the CPU baseplate (e.g., TP830).
Pay attention to polarity to avoid reverse connection.
Redundant Configuration (using SS823/SS832):
Each SD833 serves as an independent power source. Its output is connected to the input side of the SS823/SS832 voting unit.
The output of the voting unit (+24V, M) is connected to the final load system (e.g., AC 800M controller).
Key Requirement (from AC 800M manual): In high-demand controllers like AC 800M High Integrity, the redundant power supply configuration (e.g., using SS823) must strictly follow the standard diagrams provided in the manual. It is not permitted to arbitrarily alter the standard configuration by means such as adding individual circuit breakers between modules.
Operation, Maintenance, and Troubleshooting
Power-up and Operational Check
After applying input power, the green "Output OK" LED indicator on the SD833 front panel should illuminate steadily.
Use a multimeter to measure the output terminals, confirming the voltage is within the nominal range of 24V ±1%.
Preventive Maintenance
Periodic Inspection: Aligned with system maintenance cycles, check that the power module's ventilation is unobstructed and clear dust from air intake vents and heat sinks.
Connection Check: Periodically check the tightness of input and output terminal screws to prevent overheating caused by increased contact resistance due to loosening.
Spare Parts Strategy: To ensure system continuity, it is recommended that users maintain a stock of the same model SD833 as spare parts, depending on equipment criticality.
Basic Troubleshooting
If the SD833 exhibits abnormalities (e.g., LED off, abnormal output), follow these steps:
Confirm Input: Check if the upstream circuit breaker has tripped. Measure the voltage between input terminals L-N to ensure it is within the allowed range (90-132V or 180-264V).
Check Load: Temporarily disconnect all loads and measure the no-load output voltage to determine if it's a power supply fault or protection triggered by a short circuit/overload on the load side.
Check Environment: Verify that module mounting clearances meet requirements and that ambient temperature is not excessively high, causing overtemperature protection.
Replacement Test: If conditions allow, perform a replacement test with a known-good unit of the same model to quickly locate the issue.
Important Note: The SD833 is a sealed design and should not be repaired by users. Faulty modules should be referred to professional personnel for inspection or replacement.
Typical Application Scenarios
Process Industries (Chemicals, Pharmaceuticals, Water Treatment): Main power supply for medium-scale distributed control stations (DCS).
Discrete Manufacturing (Automotive, Packaging, Food & Beverage): Power supply for main PLC control cabinets of large production lines, robot control units.
Infrastructure: Power supply for building automation management centers, medium-sized substation monitoring systems.
Redundant Systems: As a standard unit in a 1+1 redundant pair, providing assurance for any control node requiring high power availability.
Comparison with Other Models in the SD83x Series
Table 2: SD83x Series Power Module Selection Reference
| Feature/Model | SD831 (3A) | SD832 (5A) | SD833 (10A) | SD834 (20A) |
| Rated Output Current | 3 A | 5 A | 10 A | 20 A |
| Rated Output Power | 72 W | 120 W | 240 W | 480 W |
| Input Voltage (AC) | 100-240V (Wide) | 100-120/200-240V | 100-120/200-240V | 100-240V (Wide) |
| Parallel Operation | Not Supported | Not Supported | Not Supported | Supported |
| DC-OK Relay | No | No | No | Yes |
| Hazardous Area Cert. | No | No | No | Class 1 Div 2 |
| Typical Efficiency | ~89% | ~90% | ~91.6% | >93% |
| Width | 50 mm | 32 mm | 60 mm | 82 mm |
| Core Value | Compact, Economical, Small Systems | Cost-effective, Standard for Medium Loads | Best Balance of Power & Cost, Mainstay for Medium Systems | Ultra-high Power, Scalable, Advanced Monitoring |
Selection Advice:
Choose SD833 when your system load requirement is between 5A and 15A, needing reliable power for multiple controller modules, communication interfaces, and a certain scale of I/O system, while pursuing optimal total cost of ownership.
For smaller, more compact systems, consider the SD832; for large, critical systems requiring future expansion, ultra-high power, or advanced monitoring functions, the SD834 should be chosen.
