DIN EN 61558-2-14:2013-09

This part of IEC 61558 deals with safety aspects of variable transformers for general applications and power supply units incorporating variable transformers for general applications. Transformers incorporating electronic circuits are also covered by this standard. The rated supply voltage does not exceed 1 000 V a.c., and the rated supply frequency does not exceed 500 Hz. This standard is applicable to transformers and power supply units (linear) with internal operational frequencies not exceeding 500 Hz. This standard used in combination with Part 2-16 for switch mode power supply units (SMPS) is also applicable to power supplies with internal operational frequencies higher than 500 Hz. In cases where the two requirements are in conflict, the most severe take precedence. This part 2-14 does not apply to transformers covered by IEC 60076-11. This part 2-14 is applicable to stationary or portable, air-cooled (natural or forced), single-phase or polyphase, independent or associated dry-type transformers: - variable auto-transformers and power supply units incorporating variable auto-transformers; - variable separating transformers and power supply units incorporating variable separating transformers; -variable isolating transformers and power supply units incorporating variable isolating transformers; -variable safety isolating transformers and power supply units incorporating variable safety isolating transformers. The windings may be encapsulated or non-encapsulated. The rated output does not exceed: - 40 kVA for single-phase variable auto-transformers and power supply units incorporating single-phase variable auto-transformers; - 200 kVA for poly-phase variable auto-transformers and power supply units incorporating poly-phase variable auto-transformers; - 1 kVA for single-phase variable separating transformers and power supply units incorporating single-phase variable separating transformers; - 5 kVA for poly-phase variable separating transformers and power supply units incorporating poly-phase variable separating transformers; - 25 kVA for single-phase variable isolating transformers and power supply units incorporating single-phase variable isolating transformers; - 40 kVA for poly-phase variable isolating transformers and power supply units incorporating poly-phase variable isolating transformers; - 10 kVA for single-phase variable safety isolating transformers and power supply units incorporating single-phase variable safety isolating transformers; - 16 kVA for poly-phase variable safety isolating transformers and power supply units incorporating poly-phase variable safety isolating transformers. This part 2-14 is applicable to transformers without limitation of the rated output subject to an agreement between the purchaser and the manufacturer. For variable auto-transformers and power supply units incorporating variable auto-transformers: - the no-load output voltage or the rated output voltage does not exceed 1 000 V a.c. or 1 415 V ripple free d.c.; - for independent auto-transformers the rated output voltage does exceed 50 V a.c or 120 V ripple-free d.c. but not exceed 250 V a.c. Variable auto-transformers and power supply units incorporating variable auto-transformers intended to be used by technically skilled or trained personnel are considered as associated transformers and associated power supply units and may have a rated output voltage less than 50 V a.c. The responsible committee is DKE/K 323 "Transformatoren, Drosseln, Netzgeräten und entsprechende Kombinationen" ("Transformers, reactors, power supply units and combinations thereof") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.