Voltage detector and insulator interface

A voltage detector comprising:

• a plurality of voltage detector units for detecting output voltages of cells and transmitting the detected results, the voltage detector units each being powered by an associated block of a plurality of blocks divided from a high voltage battery having a plurality of secondary unit cells connected in series each other;
• a voltage detector control device powered by a low voltage battery with a voltage lower than the high voltage battery for transmitting a detection instruction to the plurality of the voltage detector units;
• a communication line interconnected between the plurality of the voltage detector units and the voltage detector control device;
• an insulator interface arranged on the communication line for communicating between the plurality of the voltage detector units and the voltage detector control device in an electrically insulated manner;
• wherein
• the insulator interface has a plurality of insulator devices formed with a pair of light emitting elements and light detecting elements operated with a same voltage supply and connected to the voltage detector control device and the respective voltage detector units,
• the light emitting and detecting elements are electrically insulated and arranged so as that all of the light detecting elements can receive lights from at least the light emitting element of the insulator devices connected to the voltage detector control device,
• the voltage detector control device transmits the detection instruction including an assignment of an address of one of the blocks through the light emitting element to the plurality of the voltage detector units;
• and
• the plurality of the voltage detector units detect the output voltages of the blocks when the address of the detection instruction transmitted from the voltage detector control device through the light emitting element of the insulator device are self-addresses.