ASN 12 | 17,5 | 24 | 36 Support type current transformers Block transformers, large design DIN 42600, part 5. The current transformers are fully encapsulated in brown epoxy resin. The active part consists of one or more toroidal cores with homogeneously applied secondary winding and primary winding. The secondary terminal box can be sealed. Each secondary clamp can be screwed through directly. On delivery, the first terminal of each core is visibly connected to earth. A transformer earthing connection is located on the side of the transformer opposite the terminal box..