Pratt & Whitney Rzeszów S.A.
MAINTENANCE MANUAL
PZL-10W ENGINE
77-22-00
1992.08.28
Page 4
Export Control Classification: PL/UE 9E999
The thermocouple signal Is compared to the threshold voltage corresponding to the maximum allowed,
CTOT on the given engine rating in the temperature limitation circuit of the electronic limiter unit.
When the trend to exceed the maximum allowed levels occurs, then the control signal is being created that
comes out from the electronic limiter unit to the electrohydraulic servo valve, which will cause the
decreasing of the fuel supply to the engine. The fuel supply will be limited to such value, that no exceeding
of the maximum CTOT may occur at given engine rating (during the engine starting and at the take-off, OEl
30 min. and OEI 2.5 min.).
The conditions of proper system functioning are the worthiness of its composing elements and appropriate
insulation resistance, and so the thermocouple circuit electric matching to the electronic limiter unit
entrance circuit (i.e. appropriate electric resistance of the thermocouple circuit measured between the plug
terminals disconnected from the electronic limiter unit).
NOTE:
The engine ratings and the maximum allowed gas temperature values adjusted for these ratings
in the electronic limiter unit are presented
in 72-02-00 Section, DESCRIPTION AND
OPERATION.