The well-known crack of a rifle, whose ball came skipping along the placid surface of the strait, and a shrill yell from the island, interrupted his speech, and announced that their passage was discovered.
An arc fault circuit interrupter (AFCI) is a circuit breaker that breaks the circuit when it detects an electric arc in the circuit it protects to prevent electrical fires. An AFCI selectively distinguishes between a harmless arc (incidental to normal operation of switches, plugs, and brushed motors), and a potentially dangerous arc (that can occur, for example, in a lamp cord which has a broken conductor).
Fault indicator. A fault indicator is a device which provides visual or remote indication of a fault on the electric power system. Also called a faulted circuit indicator (FCI), the device is used in electric power distribution networks as a means of automatically detecting and identifying faults to reduce outage time.