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Panel SCCR Rating Check

Short-circuit current rating screening per NEC 409: weakest-link rating, series-tested combinations, and the available-fault verdict. 7 inputs, 5 outputs with grouped results.

Inputs

Available fault

At the panel line terminals: utility letter or the fault-current calculator.

Panel construction

MLO panels rate at the lowest branch device unless series tested.

Nameplate interrupting rating of the main device.

Weakest branch breaker, fuse, contactor, or drive in the panel.

Series rating and feeder

Tested series combination?

A manufacturer-tested main/branch series rating replaces the weakest-link value.

Listed series combination rating; 0 when no tested combination exists.

Feeder connection

Tap conductors add length and OCPD rules outside this rating.

Result

Panel SCCR
Waiting for calculation.
Weakest-link rating
Waiting for calculation.
SCCR margin
Waiting for calculation.
SCCR adequate (1=yes)
Waiting for calculation.
Needs 240.21 tap review (1=yes)
Waiting for calculation.
Screening calculation only. The panel SCCR is established by the manufacturer listing and series test data; verify against NEC 409 and UL 508A SB4, and the authority having jurisdiction governs.

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Workspace

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