INSTRUCTION MANUAL
DPS400
56-101-01180-C
1-4
Page 38
November 5, 2003
F. ENGINE PRESSURE RATIO (EPR) TEST
Note:
This test is limited by the Tester airspeed range.
(1)
Preliminary
(a)
Connect PITOT PORT (Red) to the PT7 (Hi) port of E.P.R. transmitter to be
tested.
(b)
Connect STATIC PORT (Blue) to the PT2 (Lo) port of E.P.R. transmitter to be
tested.
(2)
Test
(a)
The EPR function of the DPS400 allows the display the EPR Ratio PT7/PT2
and pressures of PT2 and PT7 individually. The units of measurement
available for the PT2 and PT7 pressure display are; inHg; mb; or altitude (ft or
M) and airspeed (kts or km/hour). To set up the EPR display to desired units
of measurement, refer to Setting the Display Units.
Note:
If the EPR data is displayed in altitude (ft) and airspeed (kts),
Table 2 can be referenced as a guide to establish the desired EPR
Ratio.
(b)
Make sure the static (Altitude or PT2) and pitot (Airspeed or PT7) pressure
combination achieves the desired EPR ratio.
ENGINE PRESSURE
RATIO
AIRSPEED (KNOTS)
Pt7 (Hi) PORT
ALTITUDE (FEET)
Pt2 (Lo) PORT
3.4 650
25,870
3.4 546
35,000
3.0 650
21,650
3.0 504
35,000
2.5 650
14,690
2.5 534
25,870
2.5 444
35,000
2.0 650
4,210
2.0 500
20,000
EPR Test
Table 2
