1500W bidirectional Zener TVS — what the ratings mean for the board
The 1.5KE180C: The clamping voltage peaks at 258.3V at the rated 6.2A pulse current — that is the ceiling the downstream silicon sees. The DO-201AA axial-lead package (DO-27 equivalent) is a through-hole part.
Obsolete — sourcing through independent channels
Littelfuse lists the 1.5KE180C as obsolete. No official successor order code is recorded in the lifecycle data. If you are qualifying a replacement, the closest functional match in the same 1.5KE family would share the same DO-201 package and 1500W rating but with a standoff voltage that matches your rail.