Introduction to the ABB SD831 Power Supply

When your control system demands a stable 24V DC source, the SD831 from ABB provides a reliable solution. This switch-mode power supply converts mains voltage to 24V DC, supporting both non-redundant and redundant setups. It meets EN 50178, EN 61131-2, and UL 508 safety standards. The unit is designed for simple DIN-rail mounting and includes a soft start feature to prevent fuse tripping.

Key Features and Technical Specs of the SD831

• Rated output current: 3 A
• Rated output power: 72 W
• Rated output voltage: 24 V DC
• Mains input voltage: 100-240 V AC or 110-300 V DC
• Efficiency: 88/89.8%
• Heat dissipation: 10/8 W
• Output voltage regulation at max current: < 50 mV / < 100 mV
• Ripple (peak to peak): < 50 mV
• Maximum ambient temperature: 55 °C
• Protection rating: IP20 according to IEC 60529

One standout spec is the SD831’s ability to accept both AC and DC input, giving you flexibility in power source selection. This feature simplifies integration in facilities with mixed power systems.

Applications and Use Cases for the SD831

In industrial automation, the SD831 powers PLCs, sensors, and actuators. It is suitable for SELV and PELV applications, ensuring operator safety. For example, in a manufacturing line, this unit can supply control cabinets where space is limited. Its compact dimensions (32 mm width) allow for high-density mounting. The unit also works in redundant configurations with diode voting units SS823 or SS832, increasing system reliability.

Installation and Setup Guide

Mount the SD831 on a standard DIN rail. Ensure proper spacing: 15 mm between units and 40 mm above/below for airflow. Connect the mains input to a TN network with over-voltage Category III protection. The secondary output is SELV/PELV accepted, so no mains filter is required. Use an external primary fuse of 10-20 A. For redundant setups, add diode voting units as recommended.

Maintenance and Reliability Tips

The SD831 requires minimal maintenance due to its robust design. Inspect the unit periodically for dust accumulation and ensure ventilation slots remain clear. Operating within the 55 °C maximum ambient temperature extends service life. The unit’s output is protected against over-current and over-voltage (< 39 V), reducing downtime risks. Regular checks of the input voltage range (100-240 V AC ±10%) help maintain stable performance.

Comparison with Similar Power Supply Units

Compared to other ABB power supplies, the SD831 offers a balanced 72 W output at 24V with 3 A current. It includes a supervision relay (No) and load sharing (No), making it ideal for dedicated single-load applications. Units like the SD832 provide higher current, but the SD831 excels in compactness and efficiency (up to 89.8%). For environments requiring marine certification, this unit holds ABS, BV, DNV-GL, and LR approvals.

Frequently Asked Questions about the SD831

Q: What is the rated output voltage of the SD831?

A: The rated output voltage is 24 V DC.

Q: Can the SD831 accept both AC and DC input?

A: Yes, it accepts 100-240 V AC and 110-300 V DC.

Q: What is the protection rating of the SD831?

A: It has IP20 protection according to IEC 60529.

Q: Does the SD831 require a mains filter?

A: No, a mains filter is not required for installation.

Q: What certifications does the SD831 hold?

A: It meets IEC 61131-2, UL 508, and EN 50178, with marine certifications from ABS, BV, DNV-GL, and LR.

Product Support and Availability

The SD831 is available through PetroPartsOnline, a trusted supplier of industrial automation parts. In stock and ready to ship, this unit supports your control system needs. Contact PetroPartsOnline for current lifecycle status and ordering details.