TB 9-6685-322-50
The change in the ice point correction is -.1. This decrease is applied to the correction chart
from the initial calibration to produce the following.
New Correction Chart
Based on Ice Point
Indication
Correction
(F)
(F)
-20
+.5
32
+.3
80
+.1
100
-.1
b. Adjustments
(1) If TI indications exceed the tolerance limitation (rejection tolerance) listed in
table 4, the TI will be rejected.
(2) If the TI indications exceed the scale deviations allowed in table 4, but do not
exceed the rejection tolerance, prepare a correction chart using values in column 4
specifying the scale corrections at each test point.
10. Alternate Temperature Calibration
a. Performance Check
(1) Place TI and appropriate standard thermometer (A3) into appropriate
temperature bath (A1 or A2).
(2) Adjust temperature bath for appropriate TI indication listed in table 4.
(3) After temperature has stabilized read TI and standard thermometer at a point
slightly above, but as near the top of the bath as possible.
Stem correction = Kn (T - t)
K = 0.00016
T = TI indication in C.
t = Average temperature of liquid column of n degrees.
n = Number of degrees on TI scale from top of liquid level to temperature indication.
(4) Compute immergent stem correction for the TI and standard as follows:
(5) Compare TI corrected temperature with standard thermometer corrected
temperature and record standard thermometer temperature.
(6) Repeat (1) and (3) through (5) above for a total of three times.
(7) Average the three temperatures recorded in (5) above.
If the average
temperature is not within the limits specified In table 4, perform 9b above.
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