Terms Relating To Pid Controllers And Controller Tuning - Emerson Tescom ER5000 Series User Manual

ER5000 — Glossary of Terms

Terms Relating to PID Controllers and Controller Tuning

D/A Cards
Acronym for Digital To Analog Card. Used in PCs and PLCs to
generate analog signals.
Daisychain
Multiple ER5000s wired together in sequence that communicate
with a single, central PC on the same RS485 network. Each
controller within the chain must be given a unique
which is done using the ERTune™ program.
Deadband
See Integral Deadband and Pulse
Derivative
The component of a controller's response that is based on the rate
of change within the system. Generally acts to dampen the effect of
Proportional and Integral and to increase system stability.
Error
The result that is generated when
Setpoint. A zero error results in no activation. A non-zero error
Node Address,
Deadband.
Feedback is subtracted from
causes the ER5000 to activate until the error is corrected. A positive
error causes the ER5000 to increase system pressure and a negative
error causes the ER5000 to decrease system pressure.
Feedback
The input sent from an internal or external sensor that indicates
the current level of the process a PID controller manages. The
controller subtracts feedback from Setpoint, generating an
and any non-zero error activates the controller.
Hazardous Location
The Hazardous locations are areas where flammable liquids, gases
or vapors or combustible dusts exist in sufficient quantities to
produce an explosion or fire. Specially designed equipment and
special installation techniques must be used in these applications,
because an electric current is present during normal operation
of the controller, so there is the potential to generate a spark. If
your application environment meets the standard for a Hazardous
Location, you MUST use model ER5050 and follow the installation
specifications outlined on page 110
operating environment.
Error
in order to provide a safe
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