MODICON 140CPS12400 Quintessence 140 Series PLC Module

140CPS12400 Common mode interference and differential mode interference is a more commonly used classification method. Common mode interference is the signal to ground potential difference, mainly by the power grid string into the ground potential difference and space electromagnetic radiation in the signal line induced by the common-state (same direction) voltage iteration of the formation. Common mode voltage is sometimes larger, especially when using poor isolation performance of the distributor power supply, transmitter output signal common mode voltage is generally higher, some can be as high as 130V or more.

140CPS12400 through the asymmetrical circuit can be converted to differential mode voltage, affecting the measurement and control signals, resulting in component damage (this is the main reason for the high damage rate of some system I / O module), this common mode interference can be DC, can also be AC. Differential mode interference refers to the role of the signal between the poles of the interference voltage, mainly by the electromagnetic field in the space between the signal coupling induction and unbalanced circuits converted to common-mode interference formed, this interference is superimposed on the signal, directly affecting the measurement and control accuracy.

140CPS12400 is generated by the power network, electrical equipment, transient processes, lightning, radio broadcasting, television, radar, high-frequency induction heating equipment, etc., usually referred to as radiation interference, the distribution is extremely complex. If the PLC system is placed in its radio frequency field, it will be subject to radiation interference, the impact of which is mainly through two paths: one is directly to the PLC internal radiation, by the circuit inductance of the interference; the second is to the PLC communication network, the radiation, by the communication line inductance of the introduction of interference. Radiation interference with the field equipment layout and equipment generated by the size of the electromagnetic field, especially the frequency, generally through the setting of shielded cables and PLC local shielding and high-voltage discharge components for protection