Automatic change-over switch control method

The present invention discloses a method for controlling an automatic transfer switch, belonging to the technical field of electrical low voltage. The method of the present invention by conventional auxiliary backup power contacts used to perform the switching, perform the actual backup power switch points / closed state monitoring, as the conversion process in the absence of fault common power supply and the standby power switch execution to be performed in the switch double sub-state of the time, the common or found to be disconnected perform backup power switch is not turned off, then the execution switch used or backup power failure, this time by the controller controlling the driving means is stopped, thereby preventing the often, the backup power supply between short circuit. The control method of the present invention can effectively prevent the automatic transfer switch handle itself appears broken, two power short problem may be caused when the contact adhesion failure.