The espresso machine has various safety devices. Apart from the fact that the pressure vessel is made of 2 mm stainless steel by a welding robot and checked for a pressure of 10 bar, there is a safety valve that opens when the pressure is 1.8 bar. There is also a safety thermostat that switches off the machine at a boiler temperature of 135 °C.
Should a malfunction occur, both safety measures ensure that the boiler cannot crack or explode in the event of a malfunction.
The line filter has 2 fuses, so that both poles are separated when switching off.
And after a machine has been built—as prescribed—the insulation resistance and the protective conductor are measured with a safety tester to ensure that the machine can be operated on the mains without any danger.
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