PLC operation data recording method based on master-slave station communication mode

Abstract

An embodiment of the invention provides a PLC operation data recording method based on a master-slave station communication mode. The PLC operation data recording method comprises the steps of: periodically transmitting channel state monitoring data frames to a target PLC; and if a channel state response data frame is received within preset time, determining that a data channel with the target PLCis in a connected state, and reading and recording operation data from the target PLC according to the master-slave station communication mode. According to the PLC operation data recording method based on the master-slave station communication mode provided by the embodiment of the invention, tamper-proof recording and transmission of key operation accumulated data can further be realized even in a place without network coverage, the functions of inquiring, accumulating, counting and the like of internal data can be realized on the basis of not changing the original program of the PLC, and the internal data can be stored in an anti-copying and anti-tampering CPU type IC card.

Description

Technical field [0001] The invention relates to the technical field of industrial automatic control, and in particular to a PLC operating data recording method based on a master-slave station communication mode. Background technique [0002] During the operation of automatic control equipment, in many applications, the charging time, high current (greater than a certain current value is regarded as a heavy load, such as 5A) of the programmable logic controller PLC and its control objects, the running time, the maximum current value Such parameters are recorded and managed, which has important reference value for equipment maintenance. [0003] In the prior art, online monitoring technology is used to record and manage PLC operating data in most scenarios. Online monitoring technology is to continuously or regularly monitor the operating data of the monitored equipment when the monitored equipment is in operation. Automatically. The inspector can simultaneously monitor the monitor...

AI Technical Summary

Problems solved by technology

Moreover, this method also needs to configure the computer operating platform required for monitoring and configuration software

[0004] However, in practical applications, leasing of equipment with PLC as the core has become a way of equipment sharing. For this scenario, there is usually no network coverage condition. The lessor and the lessee are very concerned about the operating data of the PLC equipment. To build a corresponding communication network including the upper computer to monitor the use of PLC equipment, it is necessary to modify the source program of the PLC equipment, purchase configuration software, build a communication network, etc., and some even need to modify the source program of the PLC in the equipment, resulting in system It is very complicated, and most lessees do not have such secondary development capabilities. Even with such secondary development capabilities, the cost is very high. Therefore, there is an urgent need for a simple, tamper-proof PLC operation data recording system

Images