[en] This report, modeling guidelines for the sub-group relay in ESFAS-ARC, aims at proffering the PSA analyst the guidelines for the performing the I and C modeling to satisfy the requirements of the ASME PSA standard. Especially, this document is intended to supply the guidelines for modeling the CCF of sub-group relay and the unavailability event due to test and maintenance which were missed in the previous technical report (KAERI/TR-2920/2005). In my own judgment, this document will satisfy the requirements of the ASME PSA Standard and help to construct the PSA model for ESFAS-RPS STI extension in case of following the methodology and procedures suggested by this guideline