Temperature Detectors
FUNCTIONAL USES OF TEMPERATURE DETECTORS
If the malfunction is in the circuitry and the detector itself is still functional, it may be possible
to obtain temperatures by connecting an external bridge circuit to the detector. Resistance
readings may then be taken and a corresponding temperature obtained from the detector
calibration curves.
Environmental Concerns
Ambient temperature variations will affect the accuracy and reliability of temperature detection
instrumentation.
Variations in ambient temperature can directly affect the resistance of
components in a bridge circuit and the resistance of the reference junction for a thermocouple.
In addition, ambient temperature variations can affect the calibration of electric/electronic
equipment. The effects of temperature variations are reduced by the design of the circuitry and
by maintaining the temperature detection instrumentation in the proper environment.
The presence of humidity will also affect most electrical equipment, especially electronic
equipment. High humidity causes moisture to collect on the equipment. This moisture can cause
short circuits, grounds, and corrosion, which, in turn, may damage components. The effects due
to humidity are controlled by maintaining the equipment in the proper environment.
Summary
Detector Uses Summary
Temperature detectors are used for:
-
Indication
-
Alarm functions
-
Control functions
•
If a temperature detector became
inoperative:
-
A spare detector may be used
(if installed)
-
A contact pyrometer can be
used
•
Environmental concerns:
-
Ambient temperature
-
Humidity
Rev. 0
Page 9
IC-01
