some details
The power supply is intended for an electronic system, mounted on the roof of electric train. The train is powered with 25kV/16Hz contact wire. In a case of accident, when the wire tears and falls on the train, the equipment inside the train (connected to the a.m. electronic system) and the people touching it, should not be harmed. There is no problem with the information lines - a simple optical connection can be implemented. But it is difficult to find a suitable power supply. BTW, it should be certified.
The system mounted on the roof WILL be damaged, of course. It's case must just withstand about 500A of current for 1 second before starting to melt - the protection automatic needs this time to switch off the power net.