Load control system and control method thereof

A load control system, adapted to be connected to at least one first battery and at least one second battery and to control a load to switch between a first state and a second state, comprising:

• a power switching device, including a first power input port, a second power input port and a power output port, wherein the first power input port is electrically connected to at least one first battery and the second power input port is electrically connected to at least one second battery;
• the power switching device operates in one of a first switching mode and a second switching mode, and is controllable to operate in another one of the first switching mode and the second switching mode, wherein the first power input port and the power output port are in conduction with each other in the first switching mode, and the second power input port and the power output port are in conduction with each other in the second switching mode, wherein the power supplied from the power output port is not supplied to the load;
• and
• a control device, electrically connected to the power output port to receive the power supplied from the power output port to operate;
• when the control device operates to receive a control signal, the control device would control the load to switch from one of the first state and the second state to the other one according to the received control signal, and control the power switching device to switch from one of the first switching mode and the second switching mode to the other one;
• wherein the power switching device further includes a relay which includes the first power input port, the second power input port, and the power output port;
• and
• wherein the load further includes two connecting wires;
• the load would be in the first state when the two connecting wires are open-circuited, and in the second state when the two connecting wires are short-circuited;
• the relay further includes a control port which includes two contacts electrically connected to the two connecting wires respectively;
• in the first switching mode, the two contacts are either short-circuited or open-circuited, and in the second switching mode, the two contacts are another one of being open-circuited or short-circuited.