Time division multiplexing load control system having manual switch for directly controlling loads

摘要

A time division multiplexing load control system having a central controller unit for controlling individual terminal units to connect and disconnect loads connected respectively thereto and manual switch means for directly controlling the loads without reverting to the central controller unit is disclosed. A plurality of terminal units are connected through a shared line to the central controller unit to be controlled thereby so as to turn on/off the loads connected to respective terminal units. Each terminal unit connecting the loads is provided with a load-switching circuit for actuating respective load driving relays incorporated therein to connect and disconnect the loads. The load-switching circuit includes switch means which responds to output data signal from the central controller unit to open and close the load-switching circuit for the ON/OFF drive of the load remote from the central controller unit. Also included in each load-switching circuit are manual switch means for actuating the load driving relay independently of the output signal from the controller unit and detecting means for detecting the state of the load driving relay and transmitting such state to the controller unit so that the controller unit always acknowledges the load condition, irrespective of whether the load has been driven by the controller unit or by the manual switch means manipulated by a person near the load.