Field Serviceable Repairs - Welch Allyn SureTemp 767 Technical Manual

Troubleshooting Table (continued)
SYMPTOM POSSIBLE CAUSE
Normal Instrument
mode malfunction
temperature
reading too
low
(continued)
Improper placement
of probe.
Normal Probe malfunction.
mode
temperature
reading too
high.
Instrument
malfunction
Improper technique.
Improper technique.

FIELD SERVICEABLE REPAIRS

Repairs are considered field serviceable if the repair will not alter the calibration or proper operation of
the instrument. Recalibration requires a computer-based system and is normally performed at the
factory.
All probes designed to work with the thermometer are fully interchangeable.
All components in the Model 767 Thermometer can be replaced without effecting instrument operation
or calibration. Some minor changes to the exact calibration point will be caused by changing R20,
R21 and R23, but as long as the proper type and tolerance resistors are used (0.1%, supplied by
Welch Allyn), the unit will remain within specifications.
PROCEDURE
Check calibration with Cal Key.
Probe must be under the tongue and as far back as
possible into the sublingual pocket.
Recharacterize probe. (remove completely from
instrument and re-install.)
Or change probe.
Or test calibration of entire system using 9600.
Check calibration with Cal Key.
Movement in mouth after insertion and before final
temperature is displayed can cause high readings.
Place probe quickly into sublingual pocket and hold still.
Do not place probe in mouth until display is showing
"OrL".
Technical Manual
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