Parking
There are no designated parking places at the Kaapelitehdas. There are street side parking places around the Ruoholahti area and a paid parking garage at shopping center Ruoholahti (open 06 - 22 daily). For holders of YTV travel cards (buses, metro etc), the shopping center offers 12 hour parking for 2 euros. However, there is only a limited amount of these places available, so they may be out of them when you arrive.
It is likely that all street side parking places are taken up on Friday 22nd of January until 17:00 o'clock as this is a working day and people working at Ruoholahti will use these parking places. On Saturday and Sunday there should plenty of street side parking places available. More info on parking places in Helsinki.