ABB ACS880 Series, Firmware Manual

Page: 155 / 764

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 (by default, 300 rpm) can be activated through DI4.
Note: When commissioning the PID loop, it is useful to run the motor in speed
control first using EXT1; this allows testing of the PID feedback polarity and scaling.
Once the feedback has been proven, the PID loop can be “closed” by switching to
EXT2.
￭
Default parameter settings for the PID control macro
Below is a listing of default parameter values that differ from those listed for the
Factory macro in
Parameter listing (page 174) .
Hand/Auto macro default Parameter
4.000 12.27 AI2 min
DI3 19.11 Ext1/Ext2 selection
In1 Start 20.1 Ext1 commands
Not selected 20.4 Ext1 in2 source
In1 Start 20.6 Ext2 commands
DI6 20.8 Ext2 in1 source
DI5 20.12 Run enable 1 source
PID 22.12 Speed ref2 source
DI4 22.22 Constant speed sel1
Acc/Dec time 1 23.11 Ramp set selection
Not selected 31.11 Fault reset selection
On when drive running 40.7 Set 1 PID operation mode
AI2 scaled 40.8 Set 1 feedback 1 source
Application macros 155