FI820F 3BDH000031R1 effectively disconnects the power supply from its load
The power supply usually has a protective function short circuit or overload that may damage the power supply or cause fire. Fuse and circuit breaker are two common overload protection mechanisms. [4]
A fuse contains a small piece of wire that will melt if the current is too strong. This effectively disconnects the power supply from its load and the device stops working until the problem causing the overload is identified and the fuse is replaced. Some power supplies use very thin wired links welded in place as fuses. End users can replace fuses in power units, but fuses in consumer electronics may require tools to reach and replace them.
The circuit breaker contains a component that heats, bends and triggers a spring that closes the circuit. Once the component is cooled and the problem is determined, the circuit breaker can be reset and power restored.
Some Psus use hot-melt breaks buried in transformers rather than fuses. The advantage is that, in the limited time, it allows the extraction of current is greater than the continuous current supplied by the [①③ ③ ③ ③ ⑦] length of the device. Some such circuit breakers are self-reset and some are single-use.
Some power supplies use current limiting rather than cutting off the power when overloaded. The two current limits used are electronic limits and impedance limits. The former is commonly found in laboratory Psus and the latter in power supplies with an output of less than 3 watts.
A Backflow current limiter reduces the output current to well below the maximum non-fault current.