High Voltage Coaxial Cable Pulse Capabilities

Radio Guide, or more commonly known as RG-X cable, has been a common and almost universal means of interconnect for fast, and/or impedance-controlled pulses/pulsers. For high voltage systems there is no hard and fast rule for what the capabilities of commonly available cables are capable of handling, oft times relying on the designer’s prior history with a cable type or cable manufacturer. While specific high voltage coaxial cables are theoretically available, orders can often be delayed until a sufficiently large run of cable can be placed to support the creation. Common RG coaxial cables made with Polytetrafluoroethylene (PTFE) and Polyethylene (PE) are advertised with lower voltage hold off ratings than other research shows and experimental data suggests. These coaxial cables are typically used in DC and AC applications; however, no information of high voltage hold off in pulse applications are given. This paper addresses commonly used cable types in the RG and LMR cable types with respect to DC failure, pulse failure and expected lifetime of these coaxial cables.