hello my dear friend, you have cold insulation tests without connecting to the ac line, verify with the instruments the insulation tests on the surface regulators on your output pin, you must mark it as a diode and also it is not too much to check on insulation test in the output order of the micro power_on if it is short, it should mark you as a diode all these tests you must perform it in the range of x1 of the analogue instrument ok you are greeted by the little country of northern Peru, Marshmallow myself soyyyyyyyy