DOE-HDBK-1016/1-93
ENGINEERING FLUIDS DIAGRAMS AND PRINTS
Engineering Fluid Diagrams and Prints
Indicators and Recorders
Figure 11 Indicators and Recorders
Indicators
and
recorders
are
instruments that convert the signal
generated by an instrument loop
into a readable form.
The
indicator or recorder may be
locally or board mounted, and like
modifiers and transmitters this
information is indicated by the
type of symbol used. Figure 11
provides examples of the symbols
used for indicators and recorders
and how their location is denoted.
Controllers
Controllers process the signal from
an instrument loop and use it to
position or manipulate some other
system component. Generally they
are denoted by placing a "C" in
the balloon after the controlling
parameter as shown in Figure 12.
There are controllers that serve to
process a signal and create a new
signal. These include proportional
controllers, proportional-integral
controllers, and proportional-integral-differential controllers. The symbols for these controllers
are illustrated in Figure 13. Note that these types of controllers are also called signal
conditioners.
Figure 12 Controllers
Figure 13 Signal Conditioners
PR-02
Rev. 0
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