Apparatus for power failure identification in a programmable household appliance and method for identifying power failure

In a programmable household appliance configured to be switched off by an operator deliberately even while a program is running, a power failure identification apparatus comprising:

• a power supply;
• a mains switch supplying power to the appliance from an external electrical power supply system, said mains switch electrically connected to said power supply;
• an electronic program control apparatus electrically connected to said power supply and to said mains switch, said control apparatus having a memory for recording a program status of the appliance;
• a first means for identifying an electrical variable disposed between said mains switch and the external power supply system;
• a second means for identifying an electrical variable disposed between said mains switch and the appliance;
• said first and second identification means each:
• identifying an electrical variable of at least one of:
• the external power supply system;
• and
• said power supply;
• and
• producing an output signal based upon the electrical variable;
• and
• said control apparatus programmed:
• to store the program status if the external power supply system fails;
• to compare said output signal of each of said first and second identification devices;
• to determine whether one of a failure and a change in a respective electrical variable is due:
• to a failure of the external power supply system;
• or
• to the operator deliberately switching off the appliance;
• and
• to continue running the program from a point defined by the program status once the failure of the external power supply system has ended.

A method for identifying a power failure in a programmable household appliance configured to be switched off by an operator deliberately even while a program is running, which comprises:

• connecting a first identification device between the mains switch and the external power supply system and connecting a second identification device between the mains switch and the appliance;
• supplying power to the appliance through a mains switch from an external electrical power supply system;
• storing a program status in a memory of an electronic program control apparatus if the external power supply system fails;
• identifying one of an electrical variable of the power supply system and an electrical variable of the supply system in the appliance with the first and second identification devices and producing a respective output signal from the first and second identification devices;
• determining, with the control apparatus, whether one of a failure and a change of the electrical variable is due to a failure of the external power supply system or to a deliberate switching off of the appliance by the operator by comparing the signals produced by each of the first and second identification devices;
• and
• continuing the program from the stored program status once the failure of the power supply system has ended.