Explosively triggered gas-dielectric crowbar switch.

A gas-insulated gap switch with an unusually high standoff-to-trigger voltage ratio is described. Designed to standoff 500 kV when pressurized with SF(6) at 1.5 MPa (212 psi), the switch was triggered with as little as 19.3 kV across the gap by firing a shaped charge from one electrode toward the opposite electrode. Similar air-insulated and SF(6)-insulated gaps pressurized to 83 kPa (12 psi) and designed to standoff 50 and 150 kV, respectively, were triggered with 15.4 kV across the gap by firing an ordinary RP-2 detonator from one electrode toward the other.