NEN NVN ENV 50184 : 96 C1 1997

Recommends validation grades and validation methods for the following two classes of arc welding power sources, equipment and accessories: a) equipment constructed, calibrated and used to the accuracy specified in BS 638: Part 10: 1990; b) equipment constructed in accordance with BS 638: Part 10: 1990 but calibrated to a higher standard of accuracy than required by BS 638: Part 10: 1990 and applied to tasks requiring greater precision of operation.