CROWBAR CIRCUIT VERIFICATION TESTING SYSTEM

摘要

A system is disclosed for verifying the operativeness of a crowbar circuit which normally protects an electrical device in a series circuit with a powe r supply. The crowbar circuit includes means for sensing fault current in the series circuit and a crowbar switch responds to the sensing means for protecting the electrical device by directing the fault current away from th e electrical device. The system includes verification testing means including a fuse and actuatable pneumatic switch connected together in series for, when said pneumatic switch is actuated, providing a short circuit across the crowbar switch to verify the operativeness of the crowbar circuit which, if not operative, causes the fault current to flow through and blow out the fus e.