Table 5-8. Altitude Calibration Check.

TM 9-1270-219-13&P

Table 5-8. Altitude Calibration Check.

Data Word

Pressure Input

Test

Display

Point

Ft.

Tol.

Nominal

1050.41

1000

224

1013.25

203

123

+4000

875.10

752.62

+8000

(1)

Preliminary

Tests

5-10. Testing of the Low Airspeed Indicator (LAI).

(a) Bonding Resistance Test

(b)

Current

Consumption

Test

confirm

fault

a. T e s t

Requirements.

(2) Functional Tests

r e p o r t e d by AVUM level, the LAI will be subjected to the

(a)

Calibration

and

Status

Flag

Operation

following

tests.

Any

LAI

which

fails

any

test

will

r e t u r n e d to Depot for repair.

(b) Panel Lighting

b. T e s t E q u i p m e n t R e q u i r e d .

Table 5-9. Test Equipment for LAI Testing.

NSN

Part No.

Nomenclature

4931-01-074-3322

T e s t Station ADS (LRU)

95-112-02

Voltmeter, Digital

8125A

1430-00-366-8753

Multimeter

AN/USM

233

6625-00-999-7465

(2) Set test set switch CB1 and CB2 to ON (see

LAI Preliminary Tests.

5-11.

fig.

1-32)

and

check

that

the

associated

Iamps

illuminate.

B o n d i n g R e s i s t a n c e T e s t . Using

the

Multimeter

( 3 ) Set test set switch S12 to LAI + 15V and set

set to the lowest ohms range, check that the resistance

the Multimeter to dc current. Check the

between the bonding point on the instrument bezel and

current between test points 13 (+ve) and 14

any exposed metal work on the rear connector is less

i n d i c a t e d on the Multimeter, when test set

than 0.1 ohms.

switch S14 is depressed, is less than 0.3

amperes.

( 4 ) Set test set switch S12 to LAI15V and set

b. C u r r e n t C o n s u m p t i o n T e s t .

t h e Multimeter to dc current. Check that the

current between test points 13 (+ve) and 14

i n d i c a t e d on the Multimeter, when test set

switch S15 is depressed, is less than 0.3

(1) Connect the LAI to the test equipment as

amperes.

shown in figure 5-12.

5-19