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If the updated value PV > SP, then the special function increases the value of AQ.
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If the updated value PV < SP, then the special function reduces the value of AQ.
With a disturbance, AQ continues to increase / decrease until the updated value PV again
corresponds to SP. The speed with which AQ changes depends on the parameters KC and TI. If
the input PV exceeds the parameter Max., then the updated value PV is set to the value of Max..
If the PV falls short of the parameter Min., then the updated value PV is set to the value of Min.
If the input R is set to 1, then the AQ output is reset. As long as R is set, the input A/M is
disabled.
Sampling Sampling Sampling Sampling Time Time Time Time
The sampling time is fixed at 500 ms.
Parameter Parameter Parameter Parameter sets sets sets sets
In order to simplify the use of the PI controller, the parameters for KC, TI and Dir are already
given as sets for the following applications:
Parameter Parameter Parameter Parameter set set set set Application Application Application Application example example example example Parameter Parameter Parameter Parameter KC KC KC KC Parameter Parameter Parameter Parameter TI TI TI TI
(s)
(s)
(s) (s)
Parameter Parameter Parameter Parameter
Dir
Dir
Dir Dir
Temperature fast Temperature, cooling control of
small spaces; small volumes 0,5 30 +
Temperature slow Heating, ventilation, temperature,
cooling control of large spaces;
large volumes 1,0 120 +
Pressure 1 Quick pressure change,
compressor control 3,0 5 +
Pressure 2 Slow pressure change, differential
pressure control (flow controller) 1,2 12 +
Full level 1 Vat and/or reservoir filling without
drain 1,0 1 +
Full level 2 Vat and/or reservoir filling with
drain 0,7 20 +
Characteristics Characteristics Characteristics Characteristics when when when when configuring configuring configuring configuring
Observe the Control and regulate basics
.
Control Control Control Control and and and and regulate regulate regulate regulate basics basics basics basics
Control Control Control Control and and and and regulate regulate regulate regulate
In engineering, quantities can be both controlled and regulated.
When controlling, a quantity is manipulated without being able to compensate for outside
influences. When regulating, a quantity is maintained at a specific value in order to compensate
for outside influences.
In the following example, controlling means that the person can set the heat output at a fixed
value. The heater cannot compensate for the drop in room temperature when a window is
opened.
In the example below, regulating means that the person can increase the heat output if the
room temperature drops to below 20 °C. If the room temperature rises above 20 °C, the heat
output is reduced.