The power supply as well as the connected loads are electronically protected against overload by limiting the output current to a maximum value. Power supplies differ in their overload behaviour.
You can:
1. continuously supply current
2. supply pulsed current (hiccup behaviour) or
3. switch off.
1. continuous current in case of overload:
The output voltage is regulated back in case of overload according to a fixed output characteristic that the specified maximum current flows. The different current limiting characteristics are:
(a) Fold-back
(b) Constant Current
(c) Fold-Forward
2. Pulsed current in case of overload (Hiccup behavior)
Usually the power supply has to be restarted by pressing a key or by switching the input voltage on and off.