Convert ANSi (Win 1252) to UTF8 node-red-contrib-iconv

I have file on sftp server coded in ANSi (Win 1252, have letters like ą, ć ę etc.) I use SFTP node to connect. After that I use function and take data like this (msg.payload = Buffer.from(msg.payload.filedata, 'binary'). My next node is converter (contrib-iconv). In encoding box I have written cp1250 and doesnt work, it's only change letters for example ą, ć, ę etc. to ý. I would like to convert it to utf8 and then ą will be a, ę ->e etc.