Not sure what a 'flux welder' s but if it is an arc welder always look at the inverter models. Same goes for a MIG.TIG,ARC welder. We live on the mid north coast of NSW and often get black outs for no apparent reason and only in half of our small village. This made me go out and buy a genset off fleabay and is a 5kw model. Big enough to keep our fridge and separate large freezer running in Summer.