Mom on the phone: "When I turn the oven on the electricity go out after 5 min, can you fixed it?"
Me: "How many times it happened?"
Mom: "Do not know... once maybe"
I went there at my parents home. Fluke 87V and Fluke 1507 were my weapons.
Turned the oven on, disconnected the plug. No leaking on PE, even by putting 1000V on both main wires N or L.
mmmmm...
I disconnected the PE and let the oven work. No issue... mmmmmm...
Then I went in bed... what it could be?
Next day.... mmmm let me check the differential main switch.
sorted.