... Electrical 5)UPS Industry Product Description for Toroidal transformer: Professional power supply transformer used for the field of pro-amplifier, ... UL506, UL1411, EN61558, EN6060-1, UL2601, UL544 e. Insulation Class B, Class F, Class H f. Mounting One Metal ... temperature rise)3) Inductive voltage test4) Short circle protection5) Insulation resistance6) Hi-POT test7) Packing inspection 3. USAGE ...