The measurement of spot-welding current

CURRENT is an essential factor in the complete specification of spot-welding conditions. Therefore, the need for the measurement of spot-welding currents arises, if optimum conditions determined in experimental laboratories are to be duplicated in production shops. Laboratory methods must be accurate and supplemented by facilities for ready calibration into secondary amperes. Shop methods must be convenient, reasonably accurate, and free from the possibility of accidental error. Shops find current measurement of great value in resetting welding machines for conditions which have previously been found satisfactory.