KS C IEC 61558-2-12-2022 Safety of Transforemers, Reactors, Power supply units and combination thereof — Part 2-12: Particular requirements and tests for control voltage transformers and power supply units for constant voltage
2022KS C IEC 61558-2-12-2022 Safety of Transforemers, Reactors, Power supply units and combination thereof — Part 2-12: Particular requirements and tests for control voltage transformers and power supply units for constant voltage
2017KS C IEC 61558-2-12:2017 Safety of Transforemers, Reactors, Power supply units and combination thereof — Part 2-12: Particular requirements and tests for control voltage transformers and power supply units for constant voltag
2005KS C IEC 61558-2-12:2005 Safety of power transformers, power supply units and similar devices-Part 2-12:Particular requirements for constant voltage transformers