ABB WA4-14

The mechanical latching WA4 for contactors of type AF09 to AF96 and auxiliary contactors of type NF ensures that the contactor or auxiliary contactor remains engaged even in the event of voltage drop or failure. Standard contactors can easily be converted into compact latched contactors. The WA4 block includes a mechanical latching mechanism with release via electromagnetic impulse (AC or DC pulse) or manually. The latching keeps the closed contactor in a closed state after closing, even if the supply voltage at the terminals of the contactor coil fails. The opening of the contactor occurs electrically through a pulse (AC or DC pulse) at the coil of the WA4 block (the coil is not designed for continuous operation) or manually by pressing the button on the front of the WA4 block. The WA4 block snaps onto the front of the single-tier contactor and occupies two slots in the center position. Additional auxiliary contacts can be mounted on the side of the contactor.