Monitoring arrangement for a gas turbine spark ignition system

摘要

A monitoring arrangement for a gas turbine spark ignition system in which the spark discharge current oscillates at a known frequency includes a sonic sensor accoustically coupled to the spark igniter, a filter for passing only those signals from this sensor which have a frequency corresponding to that of the discharge current and indicating means responsive to the filter output for indicating that the spark igniter is operating. An additional optical sensor may provide a signal response to a spark gap in the ignition system, signals from both sensors being required to energize the indicating means.