The Schneider Electric TeSys LA9FL4G4G is a mechanical interlock accessory for the TeSys F contactor series. It physically prevents two or more contactors from closing simultaneously, which is essential for reversing drives, star-delta starters, or any circuit where simultaneous closure would create a phase-to-phase short. This specific variant is designed to interlock three contactors mounted vertically. The interlocking type is mechanical, meaning a rigid bar or linkage connects the contactor armatures so that only one can be in the ON position at a time.
Compatibility and mounting
The LA9FL4G4G fits a specific vertical stack of three contactors. The bottom and middle positions accept LC1F185 through LC1F225 in 3-pole or 4-pole versions, or CR1F185 in 3-pole or 4-pole. The top position accepts the larger LC1F630 (3-pole or 4-pole) or LC1F800 (3-pole only), or CR1F630 (3-pole or 4-pole). Mounting position is fixed at 3 vertical — the interlock bar runs along the vertical axis of the three contactors. This is a panel-mount assembly; the contactors themselves snap onto a DIN rail or mount plate, and the interlock bridges them.