Running the AC/DC on DC

I made a simple DC power source today by connecting a 500V rectifier bridge and a 1mF, 400DVC electrolytic capacitor to mains 230VAC. The result is 327VDC which I fed into the DC/DC (which is an AC/DC) converter.

And the DC/DC nicely output 13.9 VDC so it seems to work!
Didn't try it with any load though.

More stuff arriving

Today I got the Meanwell SP-750-12 AC/DC converter that will act as a DC/DC and power all the 12V stuff in the car. I tested it on 220 VAC and it produced a nice 13.9 VDC unloaded. According to specs it will do 13.5V and 750W.
It would be fun to test it with DC input, but I haven't got a DC powersource with enough voltage yet. It needs at least 127 VDC.