I bought a few of the above board as the power supplies are available for practically nothing.
As with everything I buy I test the heck out of it. This board, as is, is incorrectly wired.
The board connects two separate power supplies together to a common output without connecting the current sharing between them. Without this net connected, the supplies operate with a significant current imbalance and cannot reach anything near the full rated capacity of both supplies simultaneously - one shuts off from over-current protection first. Beyond that, it’s just a really bad idea in general to have two low output impedance voltage sources connected in parallel that way. There’s a good reason they have a that current sharing function in the feedback loop.
So enough complaining. Here’s how to fix it:
Connect a small gauge wire between J1 pin 6 and J2 pin 6. (Pin six defined as counting along the length from the first pin, the first pin being the one with the square pad where all other have round pads)
That’s it! Now the supplies will appropriately share current within the specified tolerances of the design.