Narrative:

Given an assignment with parts ordered and on hold to replace the R48 [relay]. Deferral was updated with parts needed. It [relay] looks different than the other three [relays] installed; but match R48. Upon checking the online illustrated parts catalog (ipc) 28-22-51-006a under item-25 with company part numbers (P/north) and sub-section-25 with manufacturer's (mfg) parts number that do not cross to company part numbers; [I] was not aware that replacement relay is a non-stock part. Since pre and post-service bulletin (south/B) part numbers (P/north) are both under the same company part number item at the moment; I believed I was installing the correct part.

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Original NASA ASRS Text

Title: Inadequate information in the Illustrated Parts Catalog (IPC) led to installing a Pre-Service Bulletin R48 Relay in the 414 Power Panel of a B747-400 aircraft. A Ground Fault Interrupter (GFI) type R48 Relay associated with the right wing Main fuel tank boost pump was required.

Narrative: Given an assignment with parts ordered and on hold to replace the R48 [Relay]. Deferral was updated with parts needed. It [Relay] looks different than the other three [relays] installed; but match R48. Upon checking the online Illustrated Parts Catalog (IPC) 28-22-51-006a under Item-25 with company Part Numbers (P/N) and Sub-section-25 with Manufacturer's (MFG) Parts Number that do not cross to company Part Numbers; [I] was not aware that replacement relay is a non-stock part. Since Pre and Post-Service Bulletin (S/B) Part Numbers (P/N) are both under the same company Part Number item at the moment; I believed I was installing the correct part.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.