Application Control; Control Macros; Process Pid Control - ABB ACS380 Series Firmware Manual

76 Program features

Application control



Control macros

Control macros are predefined parameter edits and I/O configurations. See chapter
Control macros.


Process PID control

There is a built-in process PID controller in the drive. The controller can be used to
control process such as pressure or flow in the pipe or fluid level in the container.
In process PID control, a process reference (setpoint) is connected to the drive
instead of a speed reference. An actual value (process feedback) is also brought
back to the drive. The process PID control adjusts the drive speed in order to keep
the measured process quantity (actual value) at the desired level (setpoint). This
means that user does not need to set a frequency/speed/torque reference to the drive
but the drive adjust its operation according to the process PID.
The simplified block diagram below illustrates the process PID control.
Setpoint
AI1
Process
AI2
actual
values
• • •
FBA
The drive contains two complete sets of process PID controller settings that can be
alternated whenever necessary; see parameter
Note: Process PID control is only available in external control; see section
external control locations
Sleep and boost functions for process PID control
The sleep function is suitable for PID control applications where the consumption
varies, such as clean water pumping systems. When used, it stops the pump
completely during low demand, instead of running the pump slowly below its efficient
operating range. The following example visualizes the operation of the function.
Process
Filter
on page 50.
Limitation
PID
40.57 PID set1/set2
Speed, torque or
frequency
reference chain
selection.
Local and