Insulation between the primary and secondary in transformers with double insulation:
- 1 insulation layer having a thickness of at least 1 mm
- at least 2 insulation layers with a total thickness of at least 0.3 mm
- three layers provided that each combination of two layers can withstand the dielectric strength test for reinforced insulation
e) In transformers with REINFORCED INSULATION or DOUBLE INSULATION the insulation
between the primary and secondary winding shall consist-of:
-- one insulation layer having a thickness of at least 1 mm, or
-- at least two insulation layers with a total thickness of not less than 0,3 mm, or
-- three layers provided that each combination of two layers can withstand the dielectric
strength test for REINFORCED INSULATION.