Position Indicators
POSITION INDICATION CIRCUITRY
Environmental Concerns
Ambient temperature variations can affect the accuracy and reliability of certain types of position
indication instrumentation. Variations in ambient temperature can directly affect the resistance
of components in the instrumentation circuitry, and, therefore, affect the calibration of
electric/electronic equipment. The effects of temperature variations are reduced by the design
of the circuitry and by maintaining the position indication instrumentation in the proper
environment, where possible.
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, where
possible.
Summary
The accuracy and reliability of position indication instrumentation can be affected by ambient
temperature and humidity. The purposes of position indicator components are summarized
below.
Position Indicator Components Summary
Detection devices provide a method to determine the position of a valve or
control rod.
The indicating and control circuitry provides for remote indication of valve or
rod position and/or various control functions.
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IC-05