Figure 5-11. Pneumatic Connection to Water Manometer.
(4) Open the tank vent valve to return the pres-
h. Static Pressure Leak Test.
sure to ambient.
Leak tests for the EPU are performed by
Connect the EPU for test as shown in figures
monitoring leak rates on the Test Set
5-8 and 5-10.
essential that the pressure source (Tester,
P i t o t Static Systems) is isolated prior to
S e t test set switch S8 DATA WD SEL TO
monitoring the leak rate.
P A B S. S e t t e s t s e t s w i t c h S 7 R D R A L T F T
to 30. Close the tester vent valve and open
(1) Connect the EPU for test as shown in figures
the tester pressure source valve. Close the
5-8 and 5-10.
t a n k vent valve. Set the Tester, Pitot Static
Systems to the values detailed in Table 5-8.
(2) Set test set switch S8 DATA WD SEL to
P ABS a n d r e c o r d t h e D A T A W O R D d i s p l a y .
Check that the DATA WORD display on
the test set reads the values detailed in Table
Close the tester vent valve and open the
tester pressure source valve. Open the tank
Open the tank vent valve to return the pres-
(3) Apply sufficient static pressure to reduce the
sure to ambient and disconnect the pressure
t e s t set numeric readout value to 018 units
(equivalent to a pressure of 10,000 ft above
prevailing ambient pressure). Start the stop-
S w i t c h off power to the test set by setting
test set switches CB1 and CB2 to OFF and
display on the Test Set does not change by
disconnect the EPU under test from the test
more than 2 units in 3˝ minutes.