MODICON 140CPU11302 Quintessence 140 Series PLC Module

MODICON 140CPU11302 Quintessence 140 Series PLC Module

140CPU11302 interference introduced by the signal will cause I / O signal work abnormally and greatly reduce the measurement accuracy, and in serious cases will cause component damage. For poor isolation performance of the system, will also lead to mutual interference between the signals, resulting in a common ground system bus backflow, resulting in changes in logic data, error and crash. PLC control system due to signal-introduced interference caused by the number of I / O module damage is quite serious, resulting in system failure is also a lot of cases.

140CPU11302 is the interference from the grounding system confusion. Grounding is to improve the electromagnetic compatibility of electronic equipment (EMC), one of the effective means of correct grounding can not only inhibit the impact of electromagnetic interference, but also inhibit the equipment to the outside world to send out the interference; and the wrong grounding instead of the introduction of serious interference signals, so that the PLC system can not work properly.

140CPU11302 control system ground including system ground, shield ground, AC ground and protective ground, etc., grounding system confusion on the PLC system interference is mainly uneven distribution of the potential of each grounding point, there is a ground potential difference between the different grounding points, resulting in ground loop current, affecting the normal operation of the system. For example, the cable shield must be grounded at one point, if the cable shield ends A, B are grounded, there is a ground potential difference, there is a current flowing through the shield. When an abnormal state occurs, such as a lightning strike, the ground current will be greater.