Product Details
The ABB DSSR 122 48990001-NK, also cataloged as the DSSR 122 Power Supply Unit, operates as a dedicated hardware component for DC voltage regulation and bus power conditioning within ABB automation systems. Designed for DC-input and regulated DC-output applications, the module converts an incoming 24 VDC supply into a regulated 5 VDC output delivering up to 40 A to power backplane logic circuits and connected processing assemblies.
Hardware Specifications
| Parameter | Specification |
|---|---|
| Model | DSSR 122 48990001-NK |
| Brand | ABB |
| Origin | Sweden / EU |
| Weight | 2.35 kg |
| Dimensions | 162 mm x 72 mm x 238.5 mm |
| Operating Temp | Standard Industrial Grade |
| Power Consumption | 200 W output capacity (5 VDC, 40 A) |
| Input Voltage | 24 VDC |
| Output Voltage | 5 VDC (regulated) |
| Output Current | 40 A |
| Recommended Spare Fuse | 20 A (Part number 5672827-20) |
Backplane Bus Communication Velocity and Power Distribution
The DSSR 122 power supply delivers clean 5 VDC logic power directly to system backplanes, ensuring stable backplane bus communication velocity across high-density digital and analog I/O racks. Integrated active voltage regulation filters out input supply ripple and voltage transients on the primary 24 VDC bus, providing tight cross-channel noise decoupling. This continuous power stability prevents logic reset conditions and maintains deterministic frame timing across critical control system networks.
Frequently Asked Questions
Q: What size fuse is specified for protecting the input side of the DSSR 122?
A: The module relies on a 20 A fuse (ABB part number 5672827-20) for internal overcurrent and short-circuit protection.
Q: Can the 5 VDC output voltage be adjusted manually on the front panel?
A: The 5 VDC output is internally regulated to precise bus tolerances and does not require field adjustment during normal operation.
Field Installation Guidelines
- Mechanical Mounting and Thermal Orientation: Secure the DSSR 122 chassis inside the designated rack or enclosure using standard mounting hardware. Ensure vertical clearance above and below the module to allow unhindered natural convection cooling through thermal heat sink fins.
- DC Wiring and Fuse Installation: Connect input wires to the 24 VDC terminals using conductors sized appropriately for the load. Confirm that the recommended 20 A fuse (5672827-20) is seated firmly in the fuse holder before applying power.
- Grounding and Shielding: Connect the frame ground terminal directly to the central panel earth busbar with a low-impedance ground braid to minimize high-frequency common-mode noise.
- Maintenance Handling: Before removing or installing the power supply module, verify that all incoming 24 VDC primary power feeders are completely de-energized.
Additional Information
- 100% Genuine Parts: All products are original and authentic, ensuring reliable industrial performance.
- 30-Day Refund Guarantee: Return any in-stock item within 30 days in original, unopened packaging for a full refund (excluding shipping and fees).
- 12-Month Warranty: Covers defects in materials or workmanship; excludes misuse, normal wear, or unauthorized modifications.
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- Support & Contact: Technical and warranty assistance is available anytime. Contact us here: Contact.
- Purchase Guidance: Check product specifications and compatibility carefully before ordering to ensure proper application.





























