The only encoder card for ATV71 compatible with sincos encoder is VW3A3409.
Nevertheless, this encoder card cannot be placed in standard ATV71 drive. You have to use ATV71...S383 version (version that could control asynchronous or synchronous motors).
ATV71...S383 is not commercialized, unfortunately, therefore it makes sense to upgrade original assembly to ATV930+ analog encoder card.
FYI, attached is the catalog with encoder cards for ATV71.
Nevertheless, this encoder card cannot be placed in standard ATV71 drive. You have to use ATV71...S383 version (version that could control asynchronous or synchronous motors).
ATV71...S383 is not commercialized, unfortunately, therefore it makes sense to upgrade original assembly to ATV930+ analog encoder card.
FYI, attached is the catalog with encoder cards for ATV71.