Pid Control Macro - ABB ACS850 Manual

94 Application macros

PID control macro

The PID control macro is suitable for process control applications, for example
closed-loop pressure, level or flow control systems such as
• pressure boost pumps of municipal water supply systems
• level-controlling pumps of water reservoirs
• pressure boost pumps of district heating systems
• material flow control on a conveyor line.
The process reference signal is connected to analog input AI1 and the process
feedback signal to AI2. Alternatively, a direct speed reference can be given to the
drive through AI1. Then the PID controller is bypassed and the drive no longer
controls the process variable.
Selection between direct speed control (control location EXT1) and process variable
control (EXT2) is done through digital input DI3.
The stop/start signals for EXT1 and EXT2 are connected to DI1 and DI6 respectively.
A constant speed (300 rpm) can be activated through DI4.
Default parameter settings for PID control macro
Below is a listing of default parameter values that differ from those listed in chapter
Additional parameter data
Parameter
No. Name
10.04 Ext2 start func
10.05 Ext2 start in1
10.10 Fault reset sel
12.01 Ext1/Ext2 sel
13.05 AI1 min scale
13.09 AI2 max scale
13.10 AI2 min scale
21.02 Speed ref2 sel
21.04 Speed ref1/2 sel
26.02 Const speed sel1
26.06 Const speed1
(page 263).
PID control macro
default
In1
DI6
C.FALSE
DI3
0.000
1500.000
0.000
PID out
DI3
DI4
300 rpm