Is there a way to protect a DC power supply from accidental mains connection on its outputs?
Edit: The protection should not require any service i.e. a fuse replacement. Protection should kick in when mains get connected and resume proper function once the mains have been disconnected. A resettable fuse or equivalent is acceptable.
Consider the circuit below. I have a 24V power supply supplying roughly 300 mA to the load. Load is connected between nodes A and B. I want to protect the PSU from getting permanently damaged if someone connects 220 VAC mains across nodes A and B.
I can think of putting a diode which protects the PSU from half cycle of mains but next half pulse will end up destroying it. If I put another diode between DC GND and node B, the DC PSU won't be able to give any power to the load. So far I have been thinking in terms of diodes. Is there a low cost (maybe 2 USD worth of components) and practical solution to this?