Honeywell UDC 2300, Product Manual

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Function Parameter Reference Guide
128 UDC2300 Controller Product Manual 12/00
adjustable overlap (hysteresis) of the on and off states of each output. Both
Deadband and Hysteresis are separately adjustable. With no relay action the
controller will read 50 %.
Other prompts affected: “HYST” and “D BAND”
PIDA PID A is normally used for three-mode control. This means that the output
can be adjusted somewhere between 100 % and 0 %. It applies all three
control actions—Proportional (P), Integral (I), and Derivative (D)—to the
error signal.
Proportional (Gain)—Regulates the controller’s output in proportion to the
error signal (the difference between Process Variable and Setpoint).
Integral (Reset)—Regulates the controller's output to the size of the error
and the time the error has existed. (The amount of corrective action depends
on the value of proportional Gain.)
Derivative (Rate)—Regulates the controller's output in proportion to the rate
of change of the error. (The amount of corrective action depends on the
value of proportional Gain.)
NOTE: PID A should not be used for Proportional only action (that is, no integral
(reset) action). Instead, use PD+MR with rate set to 0.
PIDB
Unlike the PID A equation, the controller gives only an integral response to
a setpoint change, with no effect on the output due to the gain or rate action,
and it gives full response to PV changes. Otherwise controller action is as
described for the PID A equation. See note on PID A
PDMR
PD WITH MANUAL RESET is used whenever integral action is not
wanted for automatic control. The equation is computed with no integral
contribution. The MANUAL RESET, which is operator adjustable, is then
added to the present output to form the controller output. Switching between
manual and automatic mode will not be bumpless.
If you select PD with Manual Reset you can also configure the following
variations
• PD (Two Mode) control,
• P (Single Mode) control.
Set Rate (D) to 0.
Other prompts affected: “MANRST” in the TUNING Set Up Group.
TPSC
The THREE POSITION STEP algorithm allows the control of a valve (or
other actuator), with an electric motor driven by two controller relay
outputs; one to move the motor upscale, the other downscale without a
feedback slidewire linked to the motor shaft. The deadband and hysteresis
are adjustable in the same manner as the relay duplex output algorithm.
The Three Position Step Control algorithm provides an output display
(OUT) which is an estimated motor position since the motor is not using any
feedback. Although this output indication is only an approximation, it is