56-101-01175 Revision P Page | 61
Note:
Before beginning the test, ensure that the limits profile is set to max. This
can be
accomplished by either pressing the top right box or selecting this Menu sequence:
Main Menu, Page 2, Set up 1, Limits View/Select, Select Limits, max, Ok.
Note:
This test is limited by Test Set airspeed range (650 knots).
ENGINE PRESSURE RATIO (EPR)
Airspeed (knots)
Altitude (feet)
EPR
650
25,870
3.4
546
35,000
3.4
650
21,650
3.0
504
35,000
3.0
650
14,690
2.5
534
25,870
2.5
444
35,000
2.5
650
4,210
2.0
500
20,000
2.0
369
35,000
2.0
478
5,000
1.5
365
20,000
1.5
265
35,000
1.5
Table 9
Engine Pressure Ratio Test Table
a) From the Main Menu select aeronautical parameters by this sequence: Main Menu,
Display Setup, then choose ALT, ROC, CAS, RtCAS or ALT, CAS as desired.
b) Place the DPS1000 in Control Mode.
c) Enter the first Altitude Target value.
d) Enter the first Airspeed Target value.
e) After the DPS1000 achieves both Target values, confirm the EPR Ratio reading.
f) Repeat the process by entering Both Target values for all increments of test.
2.
Method 2:
EPR Testing using EPR Mode.
The Test Set has an actual EPR Mode that can be used to test the EPR transmitter. EPR
= Pt/Ps (where Ps= Inlet pressure and Pt=Outlet pressure). In EPR Mode the Test Set
provides display of the individual pressures for PT2 and PT7 as well as the exact EPR
Ratio resulting from the equation of PT7 / PT2. In the EPR Mode, the Static (Ps) setting is
the overriding factor versus the Pitot (Pt) or the EPR Ratio. The default unit of measure
are in inHg; however, various units of measure are available for the EPR Mode as per
Table 9.
Note:
The user can change the displayed units of measure on the Test Set by this
sequence: Main Menu, Units and then choosing from among inHg, mbar, psi,
mmHg, kPa, hPa, inH
2
O@20°C, inH
2
O@4°C, inH
2
O@60°F.
Note:
Before beginning the test, ensure that the limits profile is set to max. This
can be
accomplished by either pressing the top right box or selecting this Menu sequence:
Main Menu, Page 2, Set up 1, Limits View/Select, Select Limits, max, Ok.
Note
: This test is limited by Test Set airspeed range (650 knots).
a) From the Main Menu select EPR Mode by this sequence: Main Menu, Page 2,
Additional Functions, EPR. Then return to the Main Menu.
b) Place the Test Set in Control Mode.