scope:

NEN-EN-ISO 5826 gives specifications applicable to all transformers for resistance welding equipment with or without connected rectifier. The following types are included: - single-phase transformers for alternating welding current, typically operating at 50 Hz or 60 Hz; - single-phase transformers with connected rectifier typically operating at 50 Hz or 60 Hz; - single-phase inverter welding transformer with connected rectifier typically operating at 400 Hz to 2 kHz; - three-phase transformers with connected rectifier typically operating at 50 Hz or 60 Hz. For the purposes of this International Standard, a transformer can refer to the transformer alone or combined with other components such as a rectifier, as listed above. This International Standard applies to transformers built to protection class I or II according to IEC 61140.