Sizing barrier diode when making dual supply from two single supplies

[floppy32]

I will make a +/-15V supply for a device which requires +/-15V 3A power.
For that I will use two of this supply(their output is not DC grounded so it can be done) and two barrier diodes and wire as follows:

But how can I properly size the Schottky diodes in my case? Would two 1N5822 40V 3A Schottky suffice?

 

[FvM]

Reverse protection diodes may be necessary, if the output is loaded between +15 and -15 node and the PSUs are not starting simultaneously. Most switching regulators will short applied reverse voltage by their output rectifier, D1 and D2 would be redundant. But if you are not sure about the specific PSU, 1N5822 will well serve the purpose.

Necessity of reverse protection diodes is more often observed with linear regulators. Some types are held in shutdown if started with an injected reverse current. I had the problem with standard 7812 regulator.

 

[Easy peasy]

you are correct, two x 1N5822 40V 3A should suffice