Leakage current interrupter with sustained overvoltage and/or overcurrent protection

A circuit for interrupting power to an appliance, comprising:

• a current detector providing an imbalance signal when current through first and second power supply lines is unbalanced by more than a predetermined amount;
• an interruption switch for interrupting current flow through at least one of the first and second supply lines;
• a ground fault detection sub-circuit configured to open the interruption switch upon receipt of the imbalance signal;
• a fault-inducing switch connecting the first and second supply lines and causing a current imbalance between the first and second supply lines when closed;
• an over-voltage detection sub-circuit configured to receive a signal indicative of voltage supplied to the appliance, and further configured to close the fault-inducing switch when the supplied voltage exceeds a voltage threshold VTRIP;
• at least one TEST switch, the closure of which causes the over-voltage detection sub-circuit to receive a signal indicative of a supplied voltage exceeding VTRIP;
• and
• at least one externally-visible light-emitting component, and wherein the over-voltage detection sub-circuit is further configured:
• to determine, upon closure of the TEST switch, whether a signal corresponding to a supplied voltage exceeding VTRIP has been detected,
• to close the fault-inducing switch upon determining that a signal corresponding to a supplied voltage exceeding VTRIP has been detected, and
• to activate the at least one light-emitting component so as to indicate a malfunction upon determining that a signal corresponding to a supplied voltage exceeding VTRIP has not been detected.

A circuit for interrupting power to an appliance, comprising:

• a current detector providing an imbalance signal when current through first and second power supply lines is unbalanced by more than a predetermined amount;
• at least one interruption switch for interrupting current flow through at least one of the first and second supply lines;
• a ground fault detection sub-circuit configured to open the at least one interruption switch upon receipt of the imbalance signal;
• a fault-inducing switch connecting the first and second supply lines and causing a current imbalance between the first and second supply lines when closed;
• and
• an over-current detection sub-circuit configured to receive a signal indicative of current supplied to the appliance, and further configured to close the fault-inducing switch when the supplied current exceeds a current threshold ATRIP.

A circuit for interrupting power to an appliance, comprising:

• an interruption switch for interrupting current flow through at least one of first and second supply lines supplying power to an appliance;
• an over-voltage detection sub-circuit configured to receive a signal indicative of voltage supplied to the appliance, and further configured to open the interruption switch when the supplied voltage exceeds a voltage threshold VTRIP for a period of time tV—TRIP;
• and
• an over-current detection sub-circuit configured to receive a signal indicative of current supplied to the appliance, and further configured to open the interruption switch when the supplied current exceeds a current threshold ATRIP for a period of time tA—TRIP.

A circuit for interrupting power to an appliance, comprising:

• means for a detecting an imbalance of current flowing through first and second power supply lines supplying power to an appliance;
• means for interrupting current flow through at least one of the first and second supply lines upon detection of a current imbalance;
• means for determining when current supplied to the appliance has exceeded a current threshold ATRIP for a period of time tA—TRIP;
• and
• means for causing a current imbalance when the supplied current has exceeded ATRIP for tA—TRIP.