So the problem is about preventing electric shock. Which is not a new problem at all. Using galvanic isolation is 1 of the solution, but it's expensive. How ab

So the problem is about preventing electric shock. Which is not a new problem at all. Using galvanic isolation is 1 of the solution, but it's expensive. How about using something like RCB to detect mismatch between output current and input current. This is well tested after all