Issues and Solutions for Dealing With a Highly Capacitive Transmission Cable

The ideal transmission cable exhibits little parasitic capacitance between individual internal cable conductors and also between the conductors and the cable shielding. However, transmission cables possessing high parasitic capacitance are becoming increasingly common in the glass coating industry. Cables designed for increased flexibility and reduced costs often provide minimal spacing between the shielding and current carrying conductors. The consequence of this tight spacing and the resulting high parasitic capacitance is the potential for electrical coupling through the capacitance causing undesirable ground loops and common-mode currents. Each of these can detrimentally affect power delivery to the process and/or the performance of the film deposition process.