Issue:
Can't upgrade the STRV00121 FDM121 firmware version from v2.x.x to v 4.x.x

Product Line:
STRV00121 FDM121

Masterpact MTZ circuit breakers

Environment:
Communication modules, ULP system

Resolution:

There was a hardware change in 2018 for STRV00121 FDM121 displays.

FDM121 firmware version 003.000.013 or greater is compatible with FDM121 hardware version 3.0.0 with date code WX18141 or greater.

FDM121 with date code lower than WX18141 (hardware version 1.0.0) will have a firmware version upgrade up to V.2.3.5, it can't  be upgraded to firmware version 4 and it won't communicate with Masterpact MTZ circuit breakers.

Released for: Schneider Electric USA