Cause of disturbance is usually generated by the interference, noisy sound interference and noisy sound of the different divisions waveform properties. Wherein: by reason noisy sound generated by different discharge into noisy sound, the sound of noisy surge, high-frequency oscillation noisy sound like. Press noisy sound waveforms of different nature, is divided into continuous noisy sound, occasional noisy sound, etc., according to the noisy sound interference patterns, divided into common mode and differential mode interference interference. Common mode and differential mode interference interference is a relatively common method of classification. Total touch interference signal to ground potential difference, mainly by the string into the power grid, ground potential difference and spatial electromagnetic radiation (in the same direction) voltage superimposed on the signal line formed by the induction of common mode, sometimes large common-mode voltage, especially poor performance is the use of isolation with electrical supply room, the common-mode voltage transmitter delivered generally higher, and some can be as high as 130V or more. Common mode voltage by asymmetric circuit can be converted to differential mode voltage, direct impact on the measurement and control signals, resulting in damage to the components (that is some system I / 0 module high failure rate of the main reasons), this may be a DC common-mode interference , also for the exchange. Differential mode interference is applied between the signal interference voltage poles, mainly by the electromagnetic field coupling between the sensor signal and converts unbalanced circuit common-mode voltage disturbances formed, which allow direct signal superimposed on the direct impact on the measurement and control accuracy. Install isolation transformer can solve the above problems.
PLC Control System And The Interference Problem Drive Applications
- Jun 29, 2016-