UL508A. Per Section SB, the overall panel SCCR can be determined using the following steps:
Establish the SCCR of individual power circuit components as specified in SB4.2.
Modify the available SCCR within a portion of a circuit in the panel due to the presence of current limiting components as specified in SB4.3.
Determine the overall panel SCCR as specified in SB4.4.