Inverter malfunction protection

Claim 1

IN AN ELECTRICAL NETWORK, FIRST AND SECOND ELECTRIC VALVES, SAID VALVES EACH HAVING POWER CIRCUIT AND A CONTROL CIRCUIT AND BEING OF THE DISCONTINUOUS CONTROL TYPE IN WHICH SAID CONTROL CIRCUIT CONTROLS THE INITIATION OF CURRENT FLOW THROUGH ITS ASSOCIATED SAID POWER CIRCUIT BUT IS INEFFECTIVE TO INTERRUPT CURRENT FLOW THERETHROUGH A SOURCE OF ALTERNATING POTENTIAL SIGNALS, MEANS INCLUDING A SIGNAL CONTROL APPARATUS CONNECTING SAID SOURE TO SAID CONTROL CIRCUITS OF SAID VALVES SUCH THAT WHEN SAID SIGNALS ARE OF A FIRST POLARITY AND OF AT LEAST A FIRST MAGNITUDE SAID CONTROL CIRCUIT OF SAID FIRST VALVE WILL BE ACTUATED TO INITIATE CURRENT FLOW THROUGH SAID POWER CIRCUIT OF SAID FIRST VALVE AND SUCH THAT WHEN SAID SIGNALS ARE OF A SECOND PLURALITY AND OF AT LEAST A GIVEN MAGNITUDE SAID CONTROL CIRCUIT OF SAID SECOND VALVE WILL BE ACTUATED TO INITIATE CURRENT FLOW THROUGH SAID POWER CIRCUIT OF SAID SECOND VALVE, A CURRENT SENSOR ENERGIZED AS A CONSEQUENCE OF CURRENT FLOW THROUGH SAID POWER CIRCUITS AND CONNECTED TO SAID SIGNAL CONROL APPARATUS, SAID SENSOR BEING EFFECTIVE TO SUPPLY A FIRST AND A SECOND CONTROL POTENTIAL IN RESPONSE TO CONDUCTION OF SAID POWER CIRCUITS OF SAID FIRST AND SECOND VALVES RESPECTIVELY, SAID FIRST CONTROL POTENTIAL BEING OF SAID FIRST POLARITY AND OF A PREDETERMINED MAGNITUDE, SAID SECOND CONTROL POTENTIAL BEING OF SAID SECOND POLARITY AND OF A DESIRED MAGNITUDE, SAID SIGNAL