ABB DriveIT ACH550-01 User Manual page 314

Code Description
8121 REG BYPASS CTRL
Selects Regulator by-pass control. When enabled, Regulator by-
pass control provides a simple control mechanism without a PID
regulator.
f
OUT
f
MAX
P 8110
P 8109
P 8113
P 8112
f
MIN
• Use Regulator by-pass control only in special applications.
0 =
NO
normal PFA reference: 1106
1 =
YES
• The process PID regulator is bypassed.
Actual value of PID is used as the PFA reference (input).
Normally
• The drive uses the feedback signal defined by 4014
4114) for the PFA frequency reference.
• The figure shows the relation between the control signal 4014
FBK SEL
a three-motor system.
Example: In the diagram below, the pumping station's outlet flow is
controlled by the measured inlet flow (A).
310
A
A = No auxiliary motors running
B = One auxiliary motor running
C = Two auxiliary motors running
– Disables Regulator by-pass control. The drive uses the
– Enables Regulator by-pass control.
2 is used as the PFA reference.
EXT REF
( 4114) and the speed regulated motor's frequency in
OR
ACH550 User's Manual
Range
0...1
B C
2 .
REF SELECT
Parameter listing and descriptions
P 4014
(%)
(or
FBK SEL