Block sim safety isolating transformers 2 x 12v block sim the block sim 60va safety isolating transformer 2 x 12v is a short circuit proof safety transformer with double voltage for series or parallel circuit additionally equipped with integrated short circuit and overload protection this well designed transformer also offers very good moisture protection and low noise thanks to xtradensefill resin encapsulation up to 300 va block sim 60 60va transformer 2 x 12v