To call this toy a Megger y is a joke. Not when you consider a true megger (Crank handle) puts out so much voltage it you could read microscopic faults in the winding insulation.
A certain resistance value would advise of moisture in system and a tech could perform a remedial procedure to head off comp damage.
This device generates a whooping 500vdc.
Just enough to find grounds, True megger?
What do you think?