Abstract: An electric vehicle supply equipment receives an external AC power source. The electric vehicle supply equipment includes a relay apparatus and a controller. The relay apparatus has a master relay, an auxiliary relay, and a controllable switch. The master relay is connected to a master power loop. The controllable switch is connected in series to the auxiliary relay to form a series path and connected to an auxiliary power loop. When the controller detects the external AC power source, the controller turns on the auxiliary relay. Afterward, when the controller detects that the external AC power source is in a zero-crossing condition, the controller drives the controllable switch to be turned on. Accordingly, the relays are controlled in coordinated timing, and further the external AC power source is detected, thus implementing the zero-voltage and zero-current turning on of the relay apparatus.

Abstract: A relay detection apparatus includes at least one relay, a voltage detection module, and a voltage comparison unit. The relay has an input contact, an output normally-open contact, and an output normally-close contact. The voltage detection module has a first voltage detection unit and a second voltage detection unit. The first voltage detection unit receives a voltage of the input contact and produces a first output voltage. The second voltage detection unit receives a voltage of the output normally-close contact and produces a second output voltage. The voltage comparison unit receives the first output voltage and the second output voltage and then compares the two voltages, thus detecting normal and/or abnormal contact statuses of the input contact, the output normally-open contact, and the output normally-close contact of the relay.

Abstract: An electric vehicle supply equipment receives an external AC power source. The electric vehicle supply equipment includes a relay apparatus and a controller. The relay apparatus has a master relay, an auxiliary relay, and a controllable switch. The master relay is connected to a master power loop. The controllable switch is connected in series to the auxiliary relay to form a series path and connected to an auxiliary power loop. When the controller detects the external AC power source, the controller turns on the auxiliary relay. Afterward, when the controller detects that the external AC power source is in a zero-crossing condition, the controller drives the controllable switch to be turned on. Accordingly, the relays are controlled in coordinated timing, and further the external AC power source is detected, thus implementing the zero-voltage and zero-current turning on of the relay apparatus.

Abstract: A relay detection apparatus includes at least one relay, a voltage detection module, and a voltage comparison unit. The relay has an input contact, an output normally-open contact, and an output normally-close contact. The voltage detection module has a first voltage detection unit and a second voltage detection unit. The first voltage detection unit receives a voltage of the input contact and produces a first output voltage. The second voltage detection unit receives a voltage of the output normally-close contact and produces a second output voltage. The voltage comparison unit receives the first output voltage and the second output voltage and then compares the two voltages, thus detecting normal and/or abnormal contact statuses of the input contact, the output normally-open contact, and the output normally-close contact of the relay.