Quantcast Section V. VAP-AIR MODEL 26440001-05

 

Click here to make tpub.com your Home Page

Page Title: Section V. VAP-AIR MODEL 26440001-05
Back | Up | Next

Click here for thousands of PDF manuals

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Logistics
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
   
   

 

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Back
Figure 2-16. Schematic diagram model 04.
Up
TB-9-2920-225-34-1 100 AMP Regulator (Solid State) Manual
Next
Figure 2-17. Vap-Air model 2644000105.
TB 9-2920-225-34-1
Section V. VAP-AIR MODEL 26440001-05
(3) Place positive probe to the bottom side
2-10. General. Figure 217 is a plan view of the
of CR3. Meter should indicate low resistance.
regulator with the cover off. Figure 218 is the
(4) Reverse probes. Meter should indicate
end view of the regulator showing the receptacles
high resistance.
and the voltage adjustment point. Figure 2-19 is
(5) If other readings are obtained replace
an exploded view of the diode mounting. Figure
diode CR3 (MR1122), NSN 5961-00-103-1519
2-20 is a relay location drawing. Figure 2-21
is a view of the circuit board and transistor heat
sink. Figure 222 is a view of the circuit board
d. Relay.
showing the electrical test points. There are 12
(1) Place ohmmeter probes across relay coil
electrical test points. Figure 223 is an electrical
terminals (see fig. 220 ). Meter should read ap-
schematic diagram of the regulator. Table 28
proximately 60 ohms.
lists the resistance checks. Table 2-9 lists the
(2) Place ohmmeter probes across contactor
voltage checks. Table 2-10 is a transistor substi-
terminals (see fig. 220). Meter should read
tution list.
infinity (open circuit ).
(3) If other readings are obtained, replace
2-11. Checkout and Repair.
relay, Vap-Air part number 27124377, NSN 2920-
a. Voltage Adjustment Rheostat (R2) (power
00735-9542.
disconnected).
(4) Reinstall transistor and circuit board
mounting plate.
(1) Place ohmmeter test probes to the violet
and brown wire terminals of the rheostat (see
e. Detailed Circuit Checks.
(1) Table 2-8 contains "power off" resist-
(2) Rotate rheostat fully clockwise, reading
ance checks of the circuit (see fig. 222 for test
should be approximately 250 ohms.
points).
(3) Rotate rheostat fully counterclockwise,
(2) Table 29 contains "power on" voltage
reading should be less than 5 ohms.
checks of the circuit (see fig. 222 for test points).
(4) If other readings are obtained, replace
f. Functional Checks. Check the performance
rheostat.
of the regulator on the test stand and make final
b. Transistors.
voltage adjustments. Voltage output should read
(1) Remove transistors Q4 and Q5 (see fig.
28 volts. If the regulator does not function prop-
erly, perform the following:
(1) Check wires and connections.
(2) Position transistors as shown in figure
( 2 ) Replace circuit board, Vap-Air part
2-1, and check each separately (see fig. 22).
number 27534930.
( 3 ) If resistance values differ from the
(3) Perform bench test procedures.
above, replace the transistors through cannibaliza-
tion or requisition transistor Q4, Vap-Air part
NOTE
number 26316033-12 (2N3441), NSN 5961-00
054-4141, or transistor Q5, Vap-Air part num-
After final repair, check regulator on
ber 2631603370 (2N3773), NSN 5961-00929
the test stand.
5014 (see table 210 for substitutes).
If the regulator still does not function correctly
(4) Check the mica insulating washers be-
it will be necessary, if local skills permit, to test
tween the transistors and mounting plate. Re-
each component. All the parts should be checked
place if cracked, broken or missing. Coat washers
with an ohmmeter and the capacitors checked with
with insulation compound per MIL-S-8660, NSN
a capacitance meter. The circuit board traces
685000880-7616.
should be checked with an ohmmeter to make
c. Diode.
sure that there are no cracked traces. Traces with
(1) Remove four screws holding transistor
hairline cracks will show good at lower tempera-
and circuit board mounting plate, and move plate
tures and will tend to show open circuit at higher
to one side.
temperatures. If the board seems good at room
temperature, but the regulator still fails, this
(2) Place negative ohmmeter probe to the
could be the cause.
top side of diode CR3 (see fig. 2-19).
2-22

Privacy Statement - Press Release - Copyright Information. - Contact Us

Integrated Publishing, Inc.