Rockwell Automation 9VT201-007HTNNN, User Manual, Page: 203 / 224

Application Notes C-7
Publication 9VT-UM001D-EN-P
PI Enable
The output of the PI loop can be turned on (enabled) or turned off
(disabled). This control allows the user to determine when the PI loop is
providing part or all of the commanded speed. The logic for enabling the
PI loop is shown in below.
The drive must be running for the PI loop to be enabled. The loop will be
disabled when the drive is ramping to a stop, jogging or the signal loss
protection for the analog input(s) is sensing a loss of signal.
If a digital input has been configured to “PI Enable,” two events are
required to enable the loop: the digital input must be closed AND bit 0 of
the PI Control parameter must be = 1.
If no digital input is configured to “PI Enable,” then only the Bit 0 = 1
condition must be met. If the bit is permanently set to a “1”, then the
loop will become enabled as soon as the drive goes into “run”.
Drive
R unning
Drive
R amping
to S top
Drive
Jogging
Bit 0 of
[PI Control] = 1
(enabled) S ignal Loss
The Configured
Digital Input
is Closed
A Digital Input
is Configured
to PI Enable
"Enabled" S tatus
Digital Input
is R eflected
in [PI S tatus]
Bit 0 = 1
The PI Loop
is Enabled
PI Enabled
S pd Cmd
PI Output
PI Pre-load Value
PI Pre-load Value = 0 PI Pre-load Value > 0
Pre-load to Command S peed
PI Enabled
S pd Cmd
PI Output
S tart at S pd Cmd
-100.0 -75.0 -50.0 -25.0 0.0 25.0 50.0 75.0 100.0
N ormalized Feedback
N
ormalized
S
Q
R
T(Feedback)
-100.0
-75.0
-50.0
-25.0
0.0
25.0
50.0
75.0
100.0