Generally if the output current has exceeded the rating current, AC Power Source will be cut off in order to protect DUT and AC Power Source against the high inrush current damage. However, the high inrush current is usually happened in the beginning of the output or during a certain test period on high inrush loads such as motors, compressors and etc., but this inrush period are short. To be able to power up the loads with high inrush current, EEC AC Power Sources include the Over Current Fold Back (OC – Fold) function, apart from the features of capability to power up high inrush current loads as well high crest factor (CF). This function exists to protect against false judgment on high inrush current loads and continue to power up the load, provided the characteristic of the loads can work with this type of output given.
If load current is higher than high limit (A-Hi) and Over Current Fold Back (OC – Fold) function is active, EEC AC Power Source will automatically adjust to decrease the output voltage when DUT load is increasing in order to maintain the constant output current at high limit (A-Hi) and to enhance power up capability of the AC Power Source.
