TB 9-6685-322-50
9. Temperature Calibration
a. Performance Check
NOTE
Perform (1) through (6) below for initial calibration only. For
subsequent calibrations perform (7) below only.
(1) Assemble thermometer calibration kit as shown in figure 1.
(2) Place TI and appropriate standard thermometer (A3) into appropriate
temperature bath (A1 and A2).
(3) Adjust temperature bath for appropriate TI listed in table 4.
(4) After temperature has stabilized, compare TI indication with standard
thermometer indication and record standard thermometer indication.
NOTE
At higher temperatures oil film may blur the lower prism. This
film may be removed long enough to take reading by removing
the prism from setup, wipe clean and replace.
CAUTION
Do not attempt to remove prism from setup with bare hands.
(5) Repeat (2) and (4) above for a total of three times.
(6) Average the three indications recorded in (4) above. If average indication is not
within limits specified In column four, table 4, perform b below.
(7) If ice point correction recorded in 8a(7) above has changed from initial
calibration correction chart, apply the ice point correction to each scale point listed on the
correction chart.
Initial Calibration
Indication
Correction
(
oF)
(oF)
-20
+.6
32
+.4
80
+.2
100
.0
At the end of the calibration interval, the thermometer is checked at the ice point with the
following result:
New Correction = +.3
8
