Abnormal detection system and method

Embodiments of the invention provide an abnormal detection system and method for carrying out abnormal detection on a plurality of screw locking devices. The system comprises a station display device,a plurality of sub-communication modules and a communication bus, wherein the number of the plurality of sub-communication modules is the same as the number of the plurality of screw locking devices;each of the plurality of sub-communication modules is connected with each of the plurality of screw locking devices in a one-to-one correspondence mode; the two adjacent sub-communication modules inthe plurality of sub-communication modules are connected through the communication bus, and the plurality of sub-communication modules are all connected with the station display device; if the screw locking device does not have a fault, the screw locking device sends the self running state information to the adjacent screw locking device through the communication bus; and if the screw locking device breaks down, the screw l