19
12. Wait for U.U.T. readout to stabilize, then press HOLD key once, and wait
a few seconds. U.U.T. should read 32.0°F ±0.5°F, type J.
13. Set calibrator output to 1400°F, type J.
14. Wait for U.U.T. readout to stabilize, then press HOLD key once, and wait
a few seconds. U.U.T. should read 1400.0°F ±1.0°F, type J.
NOTE: On Model HH-22, go to step 21 to complete calibration.
On Models HH-21 and HH-23, continue calibration at step
15.
15. Replace type J cable with Type T.
16. Set calibrator output to 32°F, type T.
17. Wait for U.U.T. readout to stabilize, then press HOLD key once, and wait
a few seconds. U.U.T. should read 32.0°F ±0.5°F, type T.
18. Set calibrator output to 750°F, type T.
19. Wait for U.U.T. reading to stabilize, then press HOLD key once, and wait
a few seconds. U.U.T. should read 750.0°F ±1.0°F, type T.
20. Press HOLD key one last time. Wait for HOLD annunciator to show on
readout. (Indicates that calibration data is stored in EEPROM.)
21. Carefully remove battery cover while holding battery in place. Loss of
battery power at this time will cause loss of calibration data.
22, Remove back cover while holding battery in place.
23. Re-install shorting-plug J1 to write-protect EEPROM.
24. Turn off U.U.T. Replace rear cover and battery cover. Calibration is com-
plete.
2. DISASSEMBLYINSTRUCTIONS
Before opening the case, remove all input/output connections. This includes
input sensors, calibration cables, and the optional battery charger.
Turn the instrument face down, and remove the three Phillips head screws
from the rear cover. Lift off the rear cover. The circuit board can be lifted from
the front case after removal of the hexagonal-standoff.
NOTE: Be sure to keep the case face down during this last
step. Otherwise, the LCD and its associated hardware
may fall free and break.