Engine Pressure Ratio (Epr) - GE ADTS 542 Instruction Manual

Engine Pressure Ratio (EPR)

Engine Pressure Ratio (EPR), the ratio of Pout/Pin is sold as a software product option. Contact GE for
more details.
The ADTS may be used to check EPR sensors and indicators. Use Ps (static) for INLET pressure and Pt
(Pitot) for OUTLET pressure.
To carry out an EPR check, the display must be showing units of pressure measurement e.g. mbar,
inHg.
: Altitude correction applies to EPR values, make sure this correction does not adversely affect
NOTE
accuracy. The difference in height between the ADTS and the EPR sensor may be different to the alti-
tude correction previously set for the aircraft instruments.
The EPR function can be operated using one of two methods, as follows:
1) Direct control of Inlet pressure and target EPR value (outlet pressure is auto-set).
2) Direct control of Inlet and Outlet pressure (equivalent EPR aim is auto-set).
The actual method to be used will be specified in the aircraft maintenance manual.
: The EPR function can only be launched when you have selected 'Go to Ground' and the
NOTE
ADTS is at Ground Pressures.
Setting the EPR - method 1
1) On the "Dashboard", select "EPR". The EPR control screen appears.
2) On the EPR control screen, set the toggle control (1) for direct control of Inlet pressure and target
EPR value.
E P R (EPR)
NGINE RESSURE ATIO
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