Block rkdrte toroidal isolation transformers 40va block rkd 302x18 the block rkd toroidal isolation transformer 2 x 115v to 2 x 18v acts as a mains transformer for adjustment of the voltage and simple electrical isolation while also acting as a safety isolating transformer for the safe electrical isolation of the input and output sides the transformer may be used to set up protective separation as a protective measure in accordance with vde 0100 and is also suitable for creating selv and