from sources external to the gas turbine. By the
mounted case and coil move with the vibration.
use of these filters, you can narrow the cause of
Due to its inertia, the magnet assembly remains
vibration down to one section of an engine. On
stationary. The coil windings cut through the
the LM2500 the power turbine operates at a slower
magnetic field in the air gap, inducing a voltage
speed than the gas generator. By use of filters,
in the coils. This voltage is proportional to the
you can determine the location of the engine
velocity of vibration. You may use vibration filters
vibration. You can tell if it is from the
to filter out the frequencies that are transmitted
Figure 5-34.--Flame-detector block diagram and typical flame detector.
5-24
