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Configuration Parameter Definitions
Control Parameters Set Up Group
96
DR4500A Classic Series Circular Chart Recorder With or Without Control Product Manual
Release M
April 2017
Lower Display
Prompt
Upper Display
Range of Setting or Selection
Parameter Definition
MINorRPM
RESET UNITS
— selects units of minutes or repeat per
minutes for the I term of the PID algorithm. 20 Repeats
per Minute = 0.05 Minutes per Repeat.
RPM
REPEATS PER MINUTE
— the number of times per
minute that the proportional action is repeated by reset.
MIN
MINUTES PER REPEAT
— the time between each
repeat of the proportional action by reset.
CONT1ALG
The
CONTROL ALGORITHM
lets you select the type of
control that is best for your process.
ATTENTION
If the recorder has two controllers
(both enabled), CONT1ALG applies for controller #1
and CONT2ALG applies for controller #2.
ON-OFF
ON/OFF
is the simplest control type. The output can be
either ON (100%) or OFF (0%). The Process Variable
(PV) is compared with the setpoint (SP) to determine
the sign of the error (ERROR = PV-SP). The ON/OFF
algorithm operates on the sign of the error signal.
In Direct Acting Control, when the error signal is
positive, the output is 100%; and when the error
signal is negative, the output is 0%. If the control
action is reverse, the opposite is true. An adjustable
overlap (Hysteresis Band) is provided between the on
and off states.
Other prompts affected: “OUT HYST”
DUPLEX ON/OFF
is an extension of this algorithm
when the output is configured for Duplex. It allows the
operation of a second ON/OFF output. There is a
deadband between the operating ranges of the two
inputs and an 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: “OUT HYST” and
“DEADBAND”