POLYMER INSULATOR EXTERNAL TYPE MEDIUM VOLTAGE SEPARATORS Polymer Insulator External type medium voltage separators are manufactured with fuse and grounded with fuse. They are designed for working at medium voltage networks up to 36 kV. They are manufactured according to TSE standards and TEDAÅ? Specifications. Separators are three phased and they can be manufactured as double poled monophase upon request. Separators are used for separating transmission lines in order to perform repair and revision works at certain parts of medium voltage networks. Therefore separated line can be seen easily. Separation mechanism can be delivered as manual controlled or drive controlled.