ISO 669: 2000 Resistance welding - Resistance welding equipment - Mechanical and electrical requirements

International Standard ISO 669 was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee SC 6, Resistance welding.
This second edition cancels and replaces the first edition (ISO 669:1981), which has been technically revised.
This International Standard applies to resistance welding equipment, to guns with inbuilt transformers and to complete movable welding equipment.
The following types are included:
- single-phase equipment with alternating welding current;
- single-phase equipment with rectified welding current by rectification of the output of the welding transformer;
- single-phase equipment with inverter welding transformer;
- three-phase equipment with rectified welding current by rectification of the output of the welding transformer;
- three-phase equipment with a current rectification in the input of the welding transformer (sometimes called frequency convertor);
- three-phase equipment with inverter welding transformers.
This International Standard applies neither to welding transformers sold separately nor to safety requirements.