PURPOSE: To ensure drive control of all devices to be controlled and simplify a construction by changing over a changeover switch in response to consumed current capacity of the air conditioning equipment devices.

CONSTITUTION: There are provided a relay contact output portion 14 which are switched on only when a pulse is inputted, and a changeover switch 12 for inputting a pulse into any of the relay contact output portion 13 or the triac output portion 14. By changing over the changeover switch 12, a construction is completed only by connecting air conditioning equipment devices A, B to the relay contact output portion 13 provided consumed current capacities of the air conditioning equipment devices A, B which are desired in drive control fall within an allowable current capacity of the relay contact output portion 13. Provided the consumed current capacities of the air conditioning equipment devices A, B exceed that of the relay contact output portion 13, a relay matching to the consumed current capacities of the air conditioning equipment devices A, B is independently provided on the triac output portion 14 for satisfactory convenience.