RS485 communication adapter for power consumption information acquisition system and control method

The invention provides an RS485 communication adapter for a power consumption information acquisition system and a control method, and belongs to the field of communication. The RS485 communication adapter comprises a power supply module, a single chip microcomputer and at least three MAX485 communication chips, the MAX485 communication chips are divided into master and slave levels, and the single chip microcomputer adopts a free bus token mechanism to control the MAX485 communication chips to realize ordered data receiving and transmitting states and switching of the receiving and transmitting states. When the MAX485 communication chips enter a transmitting state, the single chip microcomputer performs isolation timing, so that the situation that a transmitting node has a fault and always occupies a channel is avoided; and when the TTL level received by the main MAX485 is "1", the bus is kept in a high level output state under the combined action of a pull-up resistor R7 and a pull-down resistor R8, so that