Redundant DC Power Supply Capacity Calculator
Compare DC load with the available capacity of parallel supply modules during normal operation and after one module fails.
Enter module configuration
Enter the manufacturer-specified capacity loss through the redundancy module.
Single-module-failure capacity
About this calculator
Estimate normal aggregate capacity and remaining capacity after one parallel supply module fails. The entered per-module rating is reduced by derating and redundancy-module loss percentages.
Method and assumptions
Effective module rating = rated current × (1 − derating) × (1 − redundancy-module loss). Normal capacity multiplies this value by all modules; single-failure capacity multiplies it by one fewer module.
The calculation does not model current-sharing behavior, a specific redundancy device, dynamic failover, or output voltage performance.
FAQs
Does the result assume perfect current sharing?
The arithmetic treats each remaining module as contributing its entered effective rating. Actual sharing depends on the modules, redundancy device, wiring, and manufacturer limits.
What is redundancy module loss?
Enter the capacity reduction specified for the redundancy module at the applicable current and temperature. Do not assume zero loss if it is not documented.
Sources
Use the exact supply and redundancy module documentation for current ratings, derating, loss, and failure-mode behavior.