Description
Product Overview
The ABB SD821, part number 3BSC610037R1, is an AC-to-DC power supply device designed for compatible ABB industrial automation and control systems. It converts an AC mains input into a regulated 24 V DC supply for supported controllers and automation equipment.
The SD821 accepts a switch-selectable 115 V AC or 230 V AC input and provides a rated output of 24 V DC at up to 2.5 A, equivalent to approximately 60 W. It is designed for DIN-rail mounting and can be used in non-redundant or redundant power configurations. For redundant applications, ABB specifies the use of a compatible SS82x power voting unit.
The SD821 is suitable for industrial control cabinets, process automation installations, and maintenance of compatible ABB control systems. Before replacement, verify the input-voltage selector, output ratings, wiring connections, mounting arrangement, and system requirements.
Product Datasheet
| Parameter | Details |
|---|---|
| Brand | ABB |
| Model | SD821 |
| Part Number | 3BSC610037R1 |
| Series | ABB AC 800M / Industrial Automation Power Supply |
| Product Name | Power Supply Device |
| Product Type | AC-to-DC power supply |
| Place of Manufacture / Origin | Verify the individual unit and its manufacturer label |
| Product Status | Depends on the supplied unit; confirm new, open-box, or used condition |
| Input Voltage | 115 V AC / 230 V AC, switch-selectable |
| Output Voltage | 24 V DC |
| Maximum Output Current | 2.5 A |
| Rated Output Power | Approximately 60 W |
| Mounting Type | DIN rail |
| Width | 50 mm |
| Weight | Approximately 0.44–0.5 kg, depending on the source and unit configuration |
| Redundancy Support | Compatible with an appropriate ABB SS82x voting unit |
| Country of Origin | Not independently confirmed for every supplied unit |
| Discontinued Status | Reported as discontinued by some suppliers; confirm current lifecycle and replacement options with ABB |
Fault Troubleshooting and Common Questions
Q1: What is the main function of the ABB SD821?
The SD821 converts 115 V AC or 230 V AC input power into a regulated 24 V DC output for compatible industrial control equipment.
Q2: What is the rated output capacity?
The rated output is 24 V DC at up to 2.5 A, providing approximately 60 W of output power.
Q3: Why is the power supply not producing 24 V DC?
Check the incoming AC supply, input-voltage selector, protective devices, terminal connections, and load condition. If the input supply is correct but the output remains absent or unstable, the power supply may require further testing or replacement.
Q4: Can two SD821 units be connected directly in parallel?
Do not assume direct parallel operation is supported. For a redundant power arrangement, use a compatible ABB SS82x voting unit and follow the applicable system wiring instructions.
Q5: Can the SD821 replace an SD822 or SD823?
Not necessarily. The SD822 is rated for 24 V DC at 5 A, while the SD823 is rated for 24 V DC at 10 A. Although these models belong to the same power-supply family, differences in output capacity and physical dimensions must be considered.
Q6: Is the SD821 still available as a new product?
Availability and lifecycle status depend on the supplier and remaining inventory. Confirm the actual unit condition, manufacturing status, and any proposed replacement before purchasing.
Safety Precautions
- Isolate the AC supply before wiring, removing, or replacing the device.
- Set the input selector to match the available supply voltage before energizing the unit.
- Verify polarity and terminal assignments before connecting the 24 V DC output.
- Do not exceed the rated output current.
- Use a compatible voting unit for redundant configurations.
- Installation and electrical testing should be performed by qualified personnel.
Recommended Related ABB Models
The following models are related power-supply or automation components for catalog research. They are not all direct replacements for the SD821; confirm electrical and system compatibility before ordering.
- SD822 – 3BSC610038R1 — 24 V DC, 5 A power supply device for applications requiring greater output current.
- SD823 – 3BSC610039R1 — 24 V DC, 10 A power supply device for higher-load applications.
- SD831 – 3BSC610064R1 — 24 V DC, 3 A power supply with a different input-voltage specification.
- SD832 – 3BSC610065R1 — 24 V DC, 5 A power supply device.
- SD833 – 3BSC610066R1 — 24 V DC, 10 A power supply device.
- SD834 – 3BSC610067R1 — 24 V DC, 20 A power supply device for higher-current applications.
- SS822 – 3BSC610042R1 — Power voting unit for compatible redundant power-supply configurations.
- SS832 – 3BSC610068R1 — 24 V DC power voting device for supported redundant arrangements.
- PM851A – 3BSE018168R1 — ABB AC 800M controller reference for industrial process control.
- PM856K01 – 3BSE018104R1 — ABB AC 800M controller kit reference.
- PM860K01 – 3BSE018100R1 — ABB AC 800M controller kit reference.
- PM861AK01 – 3BSE018105R1 — ABB AC 800M controller kit for compatible automation systems.
- PM864AK01 – 3BSE018161R1 — ABB AC 800M controller kit reference.
- DI810 – 3BSE008508R1 — Digital input module for compatible ABB S800 I/O systems.
- DO810 – 3BSE008510R1 — Digital output module for compatible ABB S800 I/O systems.
Check the exact part number, revision, output capacity, and installation requirements before selecting a replacement or related component.
