Description
3500/15 AC and DC Power Supplies
3500/15 Common mode interference and differential mode interference are a more commonly used classification. Common mode interference is the signal to the 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 with poor isolation performance of the distributor power supply, the transmitter output signal common mode voltage is generally higher, some can be as high as 130V or more.
3500/15 common mode voltage 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 inductance and by the unbalanced circuit to convert the common mode interference formed, this interference is superimposed on the signal, directly affecting the measurement and control accuracy.