56-101-00184
/
00185 Rev. I
CH. 3
September 24, 2014
Page 16 of 56
4. PRELIMINARY
A. General
The 1811HA / GA consists of a hand-operated vacuum pump and a hand-operated
pressure pump. The pressure pump is single action developing pressure on the down
stroke only while the vacuum pump is double action developing vacuum on both the up
and down stroke. Vacuum and pressure gauges, six control valves, an altimeter, a
vertical speed indicator, and an airspeed indicator are also included in the individual test
sets. There are fittings and accessories to allow connecting the aircraft pitot and static
lines. The
1811HA
has an internal electric pump with a line cord, fuse protection, and
power
ON
/
OFF
switch.
B. Operation
The following test procedures can be performed manually. The hand-operated pressure
pump is capable of producing a pressure of 15 psi and the hand vacuum pump can
supply 25 inHg. The electric internal pump on the 1811HA can produce 27 inHg of
vacuum and 15 PSI of pressure.
Note: The user should become familiar with the
1811HA
/
GA
Test Set (T/S) before attempting
any tests. To avoid erroneous test results and damaging aircraft components or the T/S
instruments, particular attention should be given to preliminary procedures.
C. Performing the Tests
Various tests, beginning with Section 5 (PRETESTS), describe the correct method of
performing the tests using the 1811HA / GA T/S in the manual mode, i.e., hand pump
operation. Tests are NOT dependent on the source of pressure or vacuum.
D. Internal Pressure Vacuum Source
Note: Number references given in parentheses refer to Figure 4 and Table 2.
If using the 1811HA internal electric pump, do the following
:
(1) Verify that the internal PUMP SWITCH (#24) is in the OFF position and the PITOT
CONTROL (#19) and STATIC CONTROL (#7) are fully closed (clockwise).
(2) Connect the LINE CORD to the POWER ENTRY MODULE (#23), 115 / 230 volt,
50-400 Hz supply.
(3) Turn internal electric PUMP SWITCH (#24) to ON position.
(4) The PRESSURE GAUGE (#18) will show the pressure available for the pitot
pressure source.
Note: The pressure relief of the internal pump setting will be approximately 5 to
15 psi but will depend on the AIRSPEED INDICATOR (#2) range.
