10. Observe and record capacitance reading
from test stand capacitance gauge in space
provided on Performance Test Sheet. Reading
should be between C(max) and C(min).
11. If the test is not within these limits and
the converter has not been purged in previous
tests, there may be moisture in the sphere. Purge
the converter and refill it with LOX, then repeat
steps 1 through 11.
12. If the converter is still not within limits,
condemn the converter.
13. Secure the tester and disconnect the cables
from the converter and tester. If the converter
passes capacitance test, carefully remove it from
the scales and allow it to remain undisturbed for
1 hour.
EVAPORATION LOSS TEST
(BUILDUP AND SUPPLY MODE)
To perform the evaporation loss test in
the buildup and supply mode, proceed as
follows:
1. At the end of the 1 hour period, gently
place the converter on the scales and record its
weight and the start time in the spaces provided
on section 8 of the Performance Test Sheet.
2. Place the converter assembly aside again
and allow it to remain undisturbed for 24
hours.
3. At the end of the 24-hour period, carefully
replace the converter on the scales.
4. Record the time and weight in the spaces
provided on the Performance Test Sheet. The 24
hour weight loss must be less than 3 pounds.
There should not be a heavy coat of frost on the
sphere.
5. If the weight loss was 3.0 pounds or less,
and there was not excessive frosting of the sphere
assembly, proceed to the flow test. If the
loss was more than 3.0 pounds, proceed to the
EVAPORATION LOSS TEST.
EVAPORATION LOSS TEST
(VENTED MODE)
Maximum allowable loss of LOX in 24 hours
is 5.0 pounds. Minimum allowable loss is defined
as the weight recorded during the buildup and
supply mode minus 0.5 pound (performed only
if converter fails evaporation loss test in buildup
and supply mode).
To perform the evaporation loss test in the
vented mode, proceed as follows:
1. With the converter still on the scales,
attach the test stand fill valve adapter (P/N
59A120-D5-10) to the fill, buildup, and vent valve
on the converter.
WARNING
VENTING A CONVERTER THAT IS IN
A BUILDUP AND SUPPLY MODE
CAUSES A BLAST OF LOX FROM
THE VENT PORT. ENSURE THAT
VENT BLAST IS DIRECTED AWAY
FROM ALL PERSONNEL, AND THAT
ADEQUATE CLOTHING AND FACIAL
PROTECTION ARE WORN.
2. Turn the knurled knob of the adapter in
until it seats. This places the converter in the
vented mode.
3. Record the time and weight in section 9 of
the Performance Test Sheet.
4. Place the converter aside and allow it to
remain undisturbed in the vented mode for 24
hours.
5. At the end of the 24-hour period, carefully
replace the converter on the scales.
6. Record the time and the converter weight
on the Performance Test Sheet. Weight loss in 24
hours should not exceed 5.0 pounds for this test
to be satisfactory.
7. If the weight loss is too much, locate the
probable cause by using the troubleshooting chart
in table 12-22.
Table 12-22.—Troubleshooting (Evaporation Loss Test)
12-31
