Rockwell Automation Liqui-Flo V2.0 AC Drive User Manual
Page 98
98
Rockwell Automation Publication D2-3518-3 - May 2013
Chapter 9
The purpose of the PI regulator is to regulate a process variable such as position,
pressure, temperature, or flow rate, by controlling speed.
There are two ways the PI regulator can be configured to operate (see parameter
124):
• Process trim
, which takes the output of the PI regulator and sums it with a
master speed reference to control the process.
• Process control
, which takes the output of the PI regulator as the speed
command. No master speed reference exists, and the PI output directly
controls the drive output.
Note that Speed Mode (80) must be set to Process PI (2).
Figure 41 - PI Control (125)
Bit 0 - PI Enable
•
Enables/disables the operation of the PI loop.
Bit 1 - PI Hold
•
Enabled = The integrator for the outer control loop is held at the
current level; that is, it will not increase.
•
Enabled = The integrator for the outer PI control loop is allowed to
increase.
Bit 2 - PI Reset
•
Enabled = The integrator for the outer PI control loop is reset to zero.
•
Disabled = The integrator for the outer PI control loop integrates
normally.
0
0
x
0
x
x
x
x
x
x
x
x
x
x
x
x
0
0
1
1
2
3
4
5
6
7
8
9
11
12
13
14
15
1 =Enabled
0 =Disabled
x =Reserved
Bit #
Factory Default Bit Values
PI Enable
PI Hold
PI Reset
Nibble 1
Nibble 2
Nibble 3
Nibble 4