The LA9FH4F4F is a TeSys F mechanical interlock from Schneider, designed to mechanically interlock three vertically mounted contactors so that only one can close at a time — preventing simultaneous closure that would short phases in a reversing or star-delta motor starter. It interlocks bottom-position LC1F115 through LC1F150 (3P or 4P) or CR1F150 (3P or 4P), middle-position LC1F115 through LC1F150 (3P or 4P) or CR1F150 (3P or 4P), and top-position LC1F265 through LC1F330 (3P or 4P) or CR1F265 (3P or 4P).
Verify the mounting position (3 vertical) and contactor range before ordering — the interlock bar geometry is specific to the LC1F115–LC1F330 stack.
Mounts in the 3-vertical position only — the interlock bar travels vertically between the three contactor armatures. The bottom and middle positions accept the smaller LC1F115–LC1F150 frames; the top position takes the larger LC1F265–LC1F330 frame. This is not a universal interlock; the contactor frame heights must match the stack.